diff --git a/packages/app/src/components/content/ContentPanel.vue b/packages/app/src/components/content/ContentPanel.vue
index 67aa918a..f9ab84cf 100644
--- a/packages/app/src/components/content/ContentPanel.vue
+++ b/packages/app/src/components/content/ContentPanel.vue
@@ -45,7 +45,7 @@
             : isDark
               ? 'text-white/40 hover:text-white/70 hover:bg-white/5'
               : 'text-gray-500 hover:text-gray-800 hover:bg-black/5'"
-          @click="tab === 'favorites' ? (activeTab = tab) : setActiveTab(tab)"
+          @click="tab === 'favorites' || tab === 'discover' ? (activeTab = tab) : setActiveTab(tab)"
         >
           {{ tabLabel(tab) }}
         </button>
@@ -168,6 +168,9 @@
           <FavoritesGrid
             v-else-if="activeTab === 'favorites'"
           />
+          <DiscoverPanel
+            v-else-if="activeTab === 'discover'"
+          />
         </ErrorBoundary>
       </div>
     </aside>
@@ -194,6 +197,7 @@ import MagazineGrid from './MagazineGrid.vue'
 import ProjectGrid from './ProjectGrid.vue'
 import NostrGrid from './NostrGrid.vue'
 import FavoritesGrid from './FavoritesGrid.vue'
+import DiscoverPanel from './DiscoverPanel.vue'
 import ErrorBoundary from '@/components/ui/ErrorBoundary.vue'
 import { useFavoritesStore } from '@/stores/favorites'
 
@@ -259,6 +263,9 @@ const displayTabs = computed(() => {
   if (favoritesStore.items.length > 0 && !tabs.includes('favorites')) {
     tabs.push('favorites')
   }
+  if (!tabs.includes('discover')) {
+    tabs.push('discover')
+  }
   return tabs
 })
 
@@ -281,6 +288,7 @@ const TAB_LABELS: Record<ContentTab, string> = {
   'design-system': 'Design',
   nostr: 'Nostr',
   favorites: 'Favorites',
+  discover: 'Discover',
 }
 
 function tabLabel(tab: ContentTab): string {
diff --git a/packages/app/src/components/content/DiscoverPanel.vue b/packages/app/src/components/content/DiscoverPanel.vue
new file mode 100644
index 00000000..da77ce4c
--- /dev/null
+++ b/packages/app/src/components/content/DiscoverPanel.vue
@@ -0,0 +1,421 @@
+<template>
+  <div class="h-full flex flex-col">
+    <div class="p-4 border-b border-white/[0.08]">
+      <h3 class="text-sm font-bold text-white/90 mb-3">Discover</h3>
+
+      <!-- Sub-tabs -->
+      <div class="flex gap-1.5 flex-wrap">
+        <button
+          v-for="tab in subTabs"
+          :key="tab.id"
+          class="text-[10px] px-2 py-1 rounded-md transition-all duration-150"
+          :class="activeSubTab === tab.id
+            ? 'nav-tab-active'
+            : 'text-white/40 hover:text-white/70 hover:bg-white/5'"
+          @click="activeSubTab = tab.id"
+        >
+          {{ tab.label }}
+        </button>
+      </div>
+    </div>
+
+    <div class="flex-1 overflow-y-auto custom-scrollbar px-4 pt-3 pb-16 space-y-2">
+      <!-- For You -->
+      <template v-if="activeSubTab === 'foryou'">
+        <div v-if="forYouItems.length === 0" class="flex flex-col items-center justify-center py-12 gap-2">
+          <svg class="w-8 h-8 text-white/10" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M11.049 2.927c.3-.921 1.603-.921 1.902 0l1.519 4.674a1 1 0 00.95.69h4.915c.969 0 1.371 1.24.588 1.81l-3.976 2.888a1 1 0 00-.363 1.118l1.518 4.674c.3.922-.755 1.688-1.538 1.118l-3.976-2.888a1 1 0 00-1.176 0l-3.976 2.888c-.783.57-1.838-.197-1.538-1.118l1.518-4.674a1 1 0 00-.363-1.118l-3.976-2.888c-.784-.57-.38-1.81.588-1.81h4.914a1 1 0 00.951-.69l1.519-4.674z" />
+          </svg>
+          <p class="text-xs text-white/30">Add favorites to get personalized suggestions</p>
+        </div>
+
+        <div
+          v-for="item in forYouItems.slice(0, 30)"
+          :key="item.id"
+          class="flex items-center gap-3 p-3 rounded-xl bg-white/[0.03] hover:bg-white/[0.07] border border-white/5 transition-all duration-150 cursor-pointer"
+        >
+          <span class="text-[10px] w-6 h-6 rounded flex items-center justify-center shrink-0" :class="typeStyle(item.type)">
+            {{ typeIcon(item.type) }}
+          </span>
+          <div class="flex-1 min-w-0">
+            <div class="text-xs font-semibold truncate text-white/80">{{ item.title }}</div>
+            <div v-if="item.subtitle" class="text-[10px] truncate text-white/40">{{ item.subtitle }}</div>
+          </div>
+          <span class="text-[8px] text-white/20 shrink-0">{{ item.type }}</span>
+        </div>
+      </template>
+
+      <!-- Recent -->
+      <template v-else-if="activeSubTab === 'recent'">
+        <div class="flex items-center justify-between mb-2">
+          <span class="text-[10px] text-white/30">{{ viewHistory.length }} items</span>
+          <button
+            v-if="viewHistory.length > 0"
+            class="text-[9px] text-red-400/50 hover:text-red-400/80 transition-colors"
+            @click="clearHistory"
+          >
+            Clear
+          </button>
+        </div>
+
+        <div v-if="viewHistory.length === 0" class="flex flex-col items-center justify-center py-12 gap-2">
+          <svg class="w-8 h-8 text-white/10" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M12 8v4l3 3m6-3a9 9 0 11-18 0 9 9 0 0118 0z" />
+          </svg>
+          <p class="text-xs text-white/30">No recently viewed items</p>
+        </div>
+
+        <div
+          v-for="entry in viewHistory"
+          :key="entry.id + entry.viewedAt"
+          class="flex items-center gap-3 p-3 rounded-xl bg-white/[0.03] hover:bg-white/[0.07] border border-white/5 transition-all duration-150 cursor-pointer"
+        >
+          <span class="text-[10px] w-6 h-6 rounded flex items-center justify-center shrink-0" :class="typeStyle(entry.type)">
+            {{ typeIcon(entry.type) }}
+          </span>
+          <div class="flex-1 min-w-0">
+            <div class="text-xs font-semibold truncate text-white/80">{{ entry.title }}</div>
+            <div v-if="entry.subtitle" class="text-[10px] truncate text-white/40">{{ entry.subtitle }}</div>
+          </div>
+          <span class="text-[8px] text-white/20 shrink-0">{{ timeAgo(entry.viewedAt) }}</span>
+        </div>
+      </template>
+
+      <!-- Trending -->
+      <template v-else-if="activeSubTab === 'trending'">
+        <div v-if="trending.length === 0" class="flex flex-col items-center justify-center py-12 gap-2">
+          <svg class="w-8 h-8 text-white/10" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M13 7h8m0 0v8m0-8l-8 8-4-4-6 6" />
+          </svg>
+          <p class="text-xs text-white/30">No trending items yet</p>
+        </div>
+
+        <div
+          v-for="item in trending"
+          :key="item.id"
+          class="flex items-center gap-3 p-3 rounded-xl bg-white/[0.03] hover:bg-white/[0.07] border border-white/5 transition-all duration-150"
+        >
+          <span class="text-[10px] w-6 h-6 rounded flex items-center justify-center shrink-0" :class="typeStyle(item.type)">
+            {{ typeIcon(item.type) }}
+          </span>
+          <div class="flex-1 min-w-0">
+            <div class="text-xs font-semibold truncate text-white/80">{{ item.title }}</div>
+          </div>
+          <span class="text-[9px] px-1.5 py-0.5 rounded bg-accent/15 text-accent/80 shrink-0">
+            {{ item.count }}x
+          </span>
+        </div>
+      </template>
+
+      <!-- Collections -->
+      <template v-else-if="activeSubTab === 'collections'">
+        <!-- Create new -->
+        <div class="flex gap-2 mb-3">
+          <input
+            v-model="newCollectionName"
+            type="text"
+            placeholder="New collection name..."
+            class="flex-1 px-3 py-2 rounded-lg text-xs bg-white/5 text-white/80 placeholder:text-white/25 outline-none focus:bg-white/10 transition-colors"
+            @keydown.enter="createNewCollection"
+          />
+          <button
+            class="px-2.5 py-2 rounded-lg text-[10px] bg-accent/15 text-accent/80 hover:bg-accent/25 transition-colors disabled:opacity-30"
+            :disabled="!newCollectionName.trim()"
+            @click="createNewCollection"
+          >
+            Create
+          </button>
+        </div>
+
+        <div v-if="collections.length === 0" class="flex flex-col items-center justify-center py-12 gap-2">
+          <svg class="w-8 h-8 text-white/10" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M19 11H5m14 0a2 2 0 012 2v6a2 2 0 01-2 2H5a2 2 0 01-2-2v-6a2 2 0 012-2m14 0V9a2 2 0 00-2-2M5 11V9a2 2 0 012-2m0 0V5a2 2 0 012-2h6a2 2 0 012 2v2M7 7h10" />
+          </svg>
+          <p class="text-xs text-white/30">No collections yet</p>
+        </div>
+
+        <div
+          v-for="col in collections"
+          :key="col.id"
+          class="rounded-xl bg-white/[0.03] border border-white/5 p-3 space-y-2"
+        >
+          <div class="flex items-center justify-between">
+            <div class="flex-1 min-w-0">
+              <p class="text-xs font-semibold text-white/80 truncate">{{ col.name }}</p>
+              <p v-if="col.description" class="text-[9px] text-white/30 truncate">{{ col.description }}</p>
+            </div>
+            <div class="flex items-center gap-1 shrink-0">
+              <span class="text-[9px] text-white/25">{{ col.items.length }} items</span>
+              <button
+                class="text-[9px] px-1.5 py-0.5 rounded text-red-400/50 hover:text-red-400/80 hover:bg-red-400/10 transition-colors"
+                @click="deleteCollection(col.id)"
+              >
+                Delete
+              </button>
+            </div>
+          </div>
+
+          <!-- Mosaic thumbnails -->
+          <div v-if="col.items.length > 0" class="grid grid-cols-4 gap-1">
+            <div
+              v-for="item in col.items.slice(0, 4)"
+              :key="item.id"
+              class="aspect-square rounded bg-white/5 flex items-center justify-center"
+            >
+              <span class="text-[8px] font-bold" :class="typeStyle(item.type)">{{ typeIcon(item.type) }}</span>
+            </div>
+          </div>
+
+          <!-- Items list -->
+          <div v-for="item in col.items" :key="item.id" class="flex items-center gap-2 text-[10px]">
+            <span :class="typeStyle(item.type)" class="w-4 h-4 rounded flex items-center justify-center text-[7px] shrink-0">{{ typeIcon(item.type) }}</span>
+            <span class="text-white/60 truncate flex-1">{{ item.title }}</span>
+            <button
+              class="text-red-400/40 hover:text-red-400/70 transition-colors text-[8px] shrink-0"
+              @click="removeFromCollection(col.id, item.id)"
+            >
+              x
+            </button>
+          </div>
+        </div>
+      </template>
+
+      <!-- Tags -->
+      <template v-else-if="activeSubTab === 'tags'">
+        <div v-if="tagCloud.length === 0" class="flex flex-col items-center justify-center py-12 gap-2">
+          <svg class="w-8 h-8 text-white/10" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M7 7h.01M7 3h5c.512 0 1.024.195 1.414.586l7 7a2 2 0 010 2.828l-7 7a2 2 0 01-2.828 0l-7-7A1.994 1.994 0 013 12V7a4 4 0 014-4z" />
+          </svg>
+          <p class="text-xs text-white/30">No tags yet</p>
+          <p class="text-[10px] text-white/20">Tag items from content cards to organize them</p>
+        </div>
+
+        <!-- Tag cloud -->
+        <div v-if="tagCloud.length > 0" class="flex flex-wrap gap-1.5 mb-4">
+          <button
+            v-for="tc in tagCloud"
+            :key="tc.tag"
+            class="text-[10px] px-2 py-1 rounded-md transition-all duration-150"
+            :class="activeTagFilter === tc.tag
+              ? 'nav-tab-active'
+              : 'text-white/40 hover:text-white/70 bg-white/5 hover:bg-white/10'"
+            @click="activeTagFilter = activeTagFilter === tc.tag ? null : tc.tag"
+          >
+            {{ tc.tag }} <span class="text-white/20 ml-0.5">{{ tc.count }}</span>
+          </button>
+        </div>
+
+        <!-- Filtered items by tag -->
+        <div v-if="activeTagFilter" class="space-y-2">
+          <p class="text-[10px] text-white/30">Items tagged "{{ activeTagFilter }}"</p>
+          <div
+            v-for="itemId in getItemsByTag(activeTagFilter)"
+            :key="itemId"
+            class="flex items-center gap-2 p-2.5 rounded-xl bg-white/[0.03] border border-white/5"
+          >
+            <span class="text-[10px] text-white/60 font-mono truncate">{{ itemId }}</span>
+            <button
+              class="text-[8px] text-red-400/50 hover:text-red-400/80 transition-colors shrink-0"
+              @click="removeTag(itemId, activeTagFilter!)"
+            >
+              untag
+            </button>
+          </div>
+        </div>
+      </template>
+
+      <!-- Smart Playlists -->
+      <template v-else-if="activeSubTab === 'playlists'">
+        <div v-if="!hasAnySongs" class="flex flex-col items-center justify-center py-12 gap-2">
+          <svg class="w-8 h-8 text-white/10" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="1.5" d="M9 19V6l12-3v13M9 19c0 1.105-1.343 2-3 2s-3-.895-3-2 1.343-2 3-2 3 .895 3 2zm12-3c0 1.105-1.343 2-3 2s-3-.895-3-2 1.343-2 3-2 3 .895 3 2zM9 10l12-3" />
+          </svg>
+          <p class="text-xs text-white/30">No music data yet</p>
+        </div>
+
+        <template v-else>
+          <!-- Recently played songs -->
+          <div v-if="recentSongs.length > 0" class="mb-4">
+            <p class="text-[10px] text-accent/60 uppercase tracking-wider font-bold mb-2">Recently Played</p>
+            <div
+              v-for="entry in recentSongs.slice(0, 10)"
+              :key="entry.id"
+              class="flex items-center gap-2 p-2 rounded-lg bg-white/[0.03] hover:bg-white/[0.07] border border-white/5 mb-1 transition-colors"
+            >
+              <span class="text-[10px] w-5 h-5 rounded flex items-center justify-center shrink-0 bg-green-500/20 text-green-400">S</span>
+              <div class="flex-1 min-w-0">
+                <p class="text-[11px] text-white/70 truncate">{{ entry.title }}</p>
+                <p v-if="entry.subtitle" class="text-[9px] text-white/30 truncate">{{ entry.subtitle }}</p>
+              </div>
+              <span class="text-[8px] text-white/20 shrink-0">{{ timeAgo(entry.viewedAt) }}</span>
+            </div>
+          </div>
+
+          <!-- Most played songs -->
+          <div v-if="mostPlayedSongs.length > 0" class="mb-4">
+            <p class="text-[10px] text-accent/60 uppercase tracking-wider font-bold mb-2">Most Played</p>
+            <div
+              v-for="item in mostPlayedSongs.slice(0, 10)"
+              :key="item.id"
+              class="flex items-center gap-2 p-2 rounded-lg bg-white/[0.03] hover:bg-white/[0.07] border border-white/5 mb-1 transition-colors"
+            >
+              <span class="text-[10px] w-5 h-5 rounded flex items-center justify-center shrink-0 bg-green-500/20 text-green-400">S</span>
+              <div class="flex-1 min-w-0">
+                <p class="text-[11px] text-white/70 truncate">{{ item.title }}</p>
+              </div>
+              <span class="text-[9px] px-1.5 py-0.5 rounded bg-green-400/15 text-green-400/80 shrink-0">{{ item.count }}x</span>
+            </div>
+          </div>
+
+          <!-- By genre -->
+          <div v-if="songsByGenre.length > 0" class="mb-4">
+            <p class="text-[10px] text-accent/60 uppercase tracking-wider font-bold mb-2">By Genre</p>
+            <div class="flex flex-wrap gap-1.5">
+              <button
+                v-for="genre in songsByGenre"
+                :key="genre.genre"
+                class="text-[10px] px-2 py-1 rounded-md bg-white/5 text-white/50 hover:text-white/70 hover:bg-white/10 transition-colors"
+              >
+                {{ genre.genre }} <span class="text-white/20">{{ genre.count }}</span>
+              </button>
+            </div>
+          </div>
+
+          <!-- By decade -->
+          <div v-if="songsByDecade.length > 0">
+            <p class="text-[10px] text-accent/60 uppercase tracking-wider font-bold mb-2">By Decade</p>
+            <div class="flex flex-wrap gap-1.5">
+              <button
+                v-for="dec in songsByDecade"
+                :key="dec.decade"
+                class="text-[10px] px-2 py-1 rounded-md bg-white/5 text-white/50 hover:text-white/70 hover:bg-white/10 transition-colors"
+              >
+                {{ dec.decade }}s <span class="text-white/20">{{ dec.count }}</span>
+              </button>
+            </div>
+          </div>
+        </template>
+      </template>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { ref, computed } from 'vue'
+import { useForYouFeed, useContentTags, useViewHistory, useTrending } from '@/composables/useContentDiscovery'
+import { useContentCollections } from '@/composables/useContentCollections'
+import { useFavoritesStore, type FavoriteType } from '@/stores/favorites'
+
+type SubTab = 'foryou' | 'recent' | 'trending' | 'collections' | 'tags' | 'playlists'
+
+const subTabs: { id: SubTab; label: string }[] = [
+  { id: 'foryou', label: 'For You' },
+  { id: 'recent', label: 'Recent' },
+  { id: 'trending', label: 'Trending' },
+  { id: 'collections', label: 'Collections' },
+  { id: 'tags', label: 'Tags' },
+  { id: 'playlists', label: 'Playlists' },
+]
+
+const activeSubTab = ref<SubTab>('foryou')
+
+// M13.1 — For You
+const { forYouItems } = useForYouFeed()
+
+// M13.2 — Tags
+const { tagCloud, getItemsByTag, removeTag } = useContentTags()
+const activeTagFilter = ref<string | null>(null)
+
+// M13.5 — Recent
+const { viewHistory, clearHistory } = useViewHistory()
+
+// M13.6 — Collections
+const { collections, createCollection, deleteCollection, removeFromCollection } = useContentCollections()
+const newCollectionName = ref('')
+
+function createNewCollection() {
+  const name = newCollectionName.value.trim()
+  if (!name) return
+  createCollection(name)
+  newCollectionName.value = ''
+}
+
+// M13.7 — Trending
+const { trending } = useTrending()
+
+// M13.3 — Smart Playlists
+const favoritesStore = useFavoritesStore()
+
+const recentSongs = computed(() =>
+  viewHistory.value.filter(h => h.type === 'song')
+)
+
+const mostPlayedSongs = computed(() =>
+  trending.value.filter(t => t.type === 'song')
+)
+
+const hasAnySongs = computed(() =>
+  recentSongs.value.length > 0 || mostPlayedSongs.value.length > 0 || favoritesStore.getFavoritesByType('song').length > 0
+)
+
+const songsByGenre = computed(() => {
+  const songFavs = favoritesStore.getFavoritesByType('song')
+  const counts = new Map<string, number>()
+  for (const fav of songFavs) {
+    const data = fav.data as { genres?: string[] } | undefined
+    for (const g of data?.genres ?? []) {
+      counts.set(g, (counts.get(g) ?? 0) + 1)
+    }
+  }
+  return [...counts.entries()]
+    .sort((a, b) => b[1] - a[1])
+    .map(([genre, count]) => ({ genre, count }))
+})
+
+const songsByDecade = computed(() => {
+  const songFavs = favoritesStore.getFavoritesByType('song')
+  const counts = new Map<number, number>()
+  for (const fav of songFavs) {
+    const data = fav.data as { year?: number } | undefined
+    if (data?.year) {
+      const decade = Math.floor(data.year / 10) * 10
+      counts.set(decade, (counts.get(decade) ?? 0) + 1)
+    }
+  }
+  return [...counts.entries()]
+    .sort((a, b) => a[0] - b[0])
+    .map(([decade, count]) => ({ decade, count }))
+})
+
+// Helpers
+function typeIcon(type: string): string {
+  const icons: Record<string, string> = {
+    film: 'F', song: 'S', podcast: 'P', book: 'B', tv: 'T', place: 'L', article: 'A',
+  }
+  return icons[type] ?? '?'
+}
+
+function typeStyle(type: string): string {
+  const colors: Record<string, string> = {
+    film: 'bg-blue-500/20 text-blue-400',
+    song: 'bg-green-500/20 text-green-400',
+    podcast: 'bg-orange-500/20 text-orange-400',
+    book: 'bg-yellow-500/20 text-yellow-400',
+    tv: 'bg-indigo-500/20 text-indigo-400',
+    place: 'bg-red-500/20 text-red-400',
+    article: 'bg-cyan-500/20 text-cyan-400',
+  }
+  return colors[type] ?? 'bg-white/10 text-white/40'
+}
+
+function timeAgo(ts: number): string {
+  const diff = Date.now() - ts
+  const mins = Math.floor(diff / 60000)
+  if (mins < 1) return 'just now'
+  if (mins < 60) return `${mins}m ago`
+  const hours = Math.floor(mins / 60)
+  if (hours < 24) return `${hours}h ago`
+  const days = Math.floor(hours / 24)
+  return `${days}d ago`
+}
+</script>
diff --git a/packages/app/src/components/content/ShareToNostr.vue b/packages/app/src/components/content/ShareToNostr.vue
new file mode 100644
index 00000000..82bceb13
--- /dev/null
+++ b/packages/app/src/components/content/ShareToNostr.vue
@@ -0,0 +1,128 @@
+<template>
+  <div v-if="showCompose" class="fixed inset-0 z-50 flex items-center justify-center bg-black/60">
+    <div class="w-full max-w-md mx-4 rounded-2xl bg-[#0a0a0a] border border-white/10 p-5 space-y-4">
+      <div class="flex items-center justify-between">
+        <h3 class="text-sm font-bold text-white/90">Share to Nostr</h3>
+        <button
+          class="p-1.5 rounded-lg text-white/40 hover:text-white/70 hover:bg-white/5 transition-colors"
+          @click="close"
+        >
+          <svg class="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+            <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M6 18L18 6M6 6l12 12" />
+          </svg>
+        </button>
+      </div>
+
+      <textarea
+        v-model="noteContent"
+        class="w-full h-32 px-3 py-2 rounded-lg text-xs bg-white/5 text-white/80 placeholder:text-white/25 outline-none focus:bg-white/10 transition-colors resize-none"
+        placeholder="Add a note about this content..."
+      />
+
+      <div class="rounded-lg bg-white/[0.03] border border-white/5 p-3">
+        <p class="text-[10px] text-white/25 mb-1">Preview</p>
+        <p class="text-[11px] text-white/60 whitespace-pre-wrap">{{ previewText }}</p>
+      </div>
+
+      <div class="flex gap-2">
+        <button
+          class="flex-1 py-2.5 rounded-lg text-xs font-medium text-white/40 hover:text-white/70 hover:bg-white/5 transition-colors"
+          @click="close"
+        >
+          Cancel
+        </button>
+        <button
+          class="flex-1 py-2.5 rounded-lg text-xs font-medium bg-accent/15 text-accent/80 hover:bg-accent/25 transition-colors disabled:opacity-30"
+          :disabled="isPublishing || !isLoggedIn"
+          @click="publish"
+        >
+          {{ isPublishing ? 'Publishing...' : 'Publish' }}
+        </button>
+      </div>
+
+      <p v-if="!isLoggedIn" class="text-[10px] text-yellow-400/60 text-center">
+        Sign in with Nostr to share
+      </p>
+
+      <p v-if="publishResult" class="text-[10px] text-center" :class="publishOk ? 'text-emerald-400/60' : 'text-red-400/60'">
+        {{ publishResult }}
+      </p>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { ref, computed } from 'vue'
+import { useNostrIdentity } from '@/composables/useNostrIdentity'
+import { useNostr } from '@/composables/useNostr'
+
+const props = defineProps<{
+  title: string
+  type: string
+  description?: string
+  url?: string
+}>()
+
+const emit = defineEmits<{ close: [] }>()
+
+const { isLoggedIn, signEvent } = useNostrIdentity()
+const { publishEvent } = useNostr()
+
+const showCompose = ref(true)
+const noteContent = ref('')
+const isPublishing = ref(false)
+const publishResult = ref('')
+const publishOk = ref(false)
+
+const previewText = computed(() => {
+  const parts: string[] = []
+  if (noteContent.value.trim()) {
+    parts.push(noteContent.value.trim())
+    parts.push('')
+  }
+  parts.push(`${props.type.charAt(0).toUpperCase() + props.type.slice(1)}: ${props.title}`)
+  if (props.description) parts.push(props.description)
+  if (props.url) parts.push(props.url)
+  return parts.join('\n')
+})
+
+function close() {
+  showCompose.value = false
+  emit('close')
+}
+
+async function publish() {
+  isPublishing.value = true
+  publishResult.value = ''
+
+  const content = previewText.value
+
+  const unsigned = {
+    kind: 1,
+    created_at: Math.floor(Date.now() / 1000),
+    tags: [] as string[][],
+    content,
+  }
+
+  const signed = await signEvent(unsigned)
+  if (!signed) {
+    isPublishing.value = false
+    publishResult.value = 'Signing failed'
+    publishOk.value = false
+    return
+  }
+
+  const results = await publishEvent(signed)
+  const successes = results.filter(r => r.success).length
+
+  isPublishing.value = false
+  if (successes > 0) {
+    publishResult.value = `Published to ${successes}/${results.length} relays`
+    publishOk.value = true
+    setTimeout(close, 1500)
+  } else {
+    publishResult.value = 'Failed to publish'
+    publishOk.value = false
+  }
+}
+</script>
diff --git a/packages/app/src/components/content/SimilarContent.vue b/packages/app/src/components/content/SimilarContent.vue
new file mode 100644
index 00000000..aa12b0d2
--- /dev/null
+++ b/packages/app/src/components/content/SimilarContent.vue
@@ -0,0 +1,38 @@
+<template>
+  <div v-if="isLoading || suggestions.length > 0" class="mt-4 pt-4 border-t border-white/[0.08]">
+    <p class="text-[10px] text-accent/60 uppercase tracking-wider font-bold mb-2">More Like This</p>
+
+    <div v-if="isLoading" class="py-3">
+      <p class="text-[10px] text-white/30">Finding similar content...</p>
+    </div>
+
+    <div v-else class="space-y-1.5">
+      <div
+        v-for="(item, i) in suggestions"
+        :key="i"
+        class="p-2.5 rounded-lg bg-white/[0.03] border border-white/5"
+      >
+        <p class="text-[11px] font-semibold text-white/80">{{ item.title }}</p>
+        <p class="text-[9px] text-white/40 mt-0.5">{{ item.reason }}</p>
+      </div>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { onMounted } from 'vue'
+import { useSimilarContent } from '@/composables/useSimilarContent'
+import type { FavoriteType } from '@/stores/favorites'
+
+const props = defineProps<{
+  itemId: string
+  title: string
+  type: FavoriteType
+}>()
+
+const { suggestions, isLoading, fetchSimilar } = useSimilarContent()
+
+onMounted(() => {
+  fetchSimilar(props.itemId, props.title, props.type)
+})
+</script>
diff --git a/packages/app/src/composables/contentFiltering.ts b/packages/app/src/composables/contentFiltering.ts
index 35ab08d9..8ffc02df 100644
--- a/packages/app/src/composables/contentFiltering.ts
+++ b/packages/app/src/composables/contentFiltering.ts
@@ -1,4 +1,4 @@
-export type ContentTab = 'film' | 'song' | 'podcast' | 'book' | 'tvshow' | 'image' | 'place' | 'news' | 'websites' | 'magazine' | 'code' | 'design-system' | 'nostr' | 'favorites'
+export type ContentTab = 'film' | 'song' | 'podcast' | 'book' | 'tvshow' | 'image' | 'place' | 'news' | 'websites' | 'magazine' | 'code' | 'design-system' | 'nostr' | 'favorites' | 'discover'
 
 export interface MagazineSection {
   title: string
diff --git a/packages/app/src/composables/useContentCollections.ts b/packages/app/src/composables/useContentCollections.ts
new file mode 100644
index 00000000..67eb533f
--- /dev/null
+++ b/packages/app/src/composables/useContentCollections.ts
@@ -0,0 +1,89 @@
+import { ref } from 'vue'
+import type { FavoriteType } from '@/stores/favorites'
+
+const STORAGE_KEY = 'aiui-content-collections'
+
+export interface CollectionItem {
+  id: string
+  type: FavoriteType
+  title: string
+}
+
+export interface ContentCollection {
+  id: string
+  name: string
+  description: string
+  items: CollectionItem[]
+  createdAt: number
+  updatedAt: number
+}
+
+const collections = ref<ContentCollection[]>([])
+
+function load() {
+  try {
+    const stored = localStorage.getItem(STORAGE_KEY)
+    if (stored) collections.value = JSON.parse(stored)
+  } catch { /* ignore */ }
+}
+
+function save() {
+  localStorage.setItem(STORAGE_KEY, JSON.stringify(collections.value))
+}
+
+load()
+
+export function useContentCollections() {
+  function createCollection(name: string, description = ''): ContentCollection {
+    const collection: ContentCollection = {
+      id: crypto.randomUUID(),
+      name,
+      description,
+      items: [],
+      createdAt: Date.now(),
+      updatedAt: Date.now(),
+    }
+    collections.value.push(collection)
+    save()
+    return collection
+  }
+
+  function deleteCollection(id: string) {
+    collections.value = collections.value.filter(c => c.id !== id)
+    save()
+  }
+
+  function addToCollection(collectionId: string, item: CollectionItem) {
+    const collection = collections.value.find(c => c.id === collectionId)
+    if (!collection) return
+    if (collection.items.find(i => i.id === item.id)) return
+    collection.items.push(item)
+    collection.updatedAt = Date.now()
+    save()
+  }
+
+  function removeFromCollection(collectionId: string, itemId: string) {
+    const collection = collections.value.find(c => c.id === collectionId)
+    if (!collection) return
+    collection.items = collection.items.filter(i => i.id !== itemId)
+    collection.updatedAt = Date.now()
+    save()
+  }
+
+  function renameCollection(id: string, name: string) {
+    const collection = collections.value.find(c => c.id === id)
+    if (!collection) return
+    collection.name = name
+    collection.updatedAt = Date.now()
+    save()
+  }
+
+  return {
+    collections,
+    createCollection,
+    deleteCollection,
+    addToCollection,
+    removeFromCollection,
+    renameCollection,
+  }
+}
diff --git a/packages/app/src/composables/useContentDiscovery.ts b/packages/app/src/composables/useContentDiscovery.ts
new file mode 100644
index 00000000..9e29fb79
--- /dev/null
+++ b/packages/app/src/composables/useContentDiscovery.ts
@@ -0,0 +1,231 @@
+import { ref, computed } from 'vue'
+import { useFavoritesStore, type FavoriteItem, type FavoriteType } from '@/stores/favorites'
+
+// M13.1 — "For You" feed
+export function useForYouFeed() {
+  const favoritesStore = useFavoritesStore()
+
+  const forYouItems = computed(() => {
+    const items = favoritesStore.sortedItems
+    if (items.length === 0) return []
+
+    // Build frequency map by type
+    const typeFreq = new Map<FavoriteType, number>()
+    for (const item of items) {
+      typeFreq.set(item.type, (typeFreq.get(item.type) ?? 0) + 1)
+    }
+
+    // Sort types by frequency (most favorited first)
+    const sortedTypes = [...typeFreq.entries()]
+      .sort((a, b) => b[1] - a[1])
+      .map(([type]) => type)
+
+    // Return items prioritized by favorite frequency, most recent first
+    return [...items].sort((a, b) => {
+      const aRank = sortedTypes.indexOf(a.type)
+      const bRank = sortedTypes.indexOf(b.type)
+      if (aRank !== bRank) return aRank - bRank
+      return b.savedAt - a.savedAt
+    })
+  })
+
+  return { forYouItems }
+}
+
+// M13.2 — Content tagging
+const TAGS_STORAGE_KEY = 'aiui-content-tags'
+
+export interface ContentTag {
+  itemId: string
+  tags: string[]
+}
+
+const contentTags = ref<Map<string, string[]>>(new Map())
+
+function loadTags() {
+  try {
+    const stored = localStorage.getItem(TAGS_STORAGE_KEY)
+    if (stored) {
+      const entries = JSON.parse(stored) as [string, string[]][]
+      contentTags.value = new Map(entries)
+    }
+  } catch { /* ignore */ }
+}
+
+function saveTags() {
+  localStorage.setItem(TAGS_STORAGE_KEY, JSON.stringify([...contentTags.value.entries()]))
+}
+
+loadTags()
+
+export function useContentTags() {
+  function getTagsForItem(itemId: string): string[] {
+    return contentTags.value.get(itemId) ?? []
+  }
+
+  function addTag(itemId: string, tag: string) {
+    const tags = getTagsForItem(itemId)
+    if (!tags.includes(tag)) {
+      contentTags.value.set(itemId, [...tags, tag])
+      saveTags()
+    }
+  }
+
+  function removeTag(itemId: string, tag: string) {
+    const tags = getTagsForItem(itemId).filter(t => t !== tag)
+    if (tags.length === 0) {
+      contentTags.value.delete(itemId)
+    } else {
+      contentTags.value.set(itemId, tags)
+    }
+    saveTags()
+  }
+
+  const allTags = computed(() => {
+    const tagSet = new Set<string>()
+    for (const tags of contentTags.value.values()) {
+      for (const tag of tags) tagSet.add(tag)
+    }
+    return [...tagSet].sort()
+  })
+
+  const tagCloud = computed(() => {
+    const counts = new Map<string, number>()
+    for (const tags of contentTags.value.values()) {
+      for (const tag of tags) {
+        counts.set(tag, (counts.get(tag) ?? 0) + 1)
+      }
+    }
+    return [...counts.entries()]
+      .sort((a, b) => b[1] - a[1])
+      .map(([tag, count]) => ({ tag, count }))
+  })
+
+  function getItemsByTag(tag: string): string[] {
+    const ids: string[] = []
+    for (const [id, tags] of contentTags.value.entries()) {
+      if (tags.includes(tag)) ids.push(id)
+    }
+    return ids
+  }
+
+  return {
+    contentTags,
+    allTags,
+    tagCloud,
+    getTagsForItem,
+    addTag,
+    removeTag,
+    getItemsByTag,
+  }
+}
+
+// M13.5 — Recently viewed history
+const HISTORY_STORAGE_KEY = 'aiui-view-history'
+const MAX_HISTORY = 50
+
+export interface HistoryEntry {
+  id: string
+  type: FavoriteType
+  title: string
+  subtitle?: string
+  viewedAt: number
+}
+
+const viewHistory = ref<HistoryEntry[]>([])
+
+function loadHistory() {
+  try {
+    const stored = localStorage.getItem(HISTORY_STORAGE_KEY)
+    if (stored) viewHistory.value = JSON.parse(stored)
+  } catch { /* ignore */ }
+}
+
+function saveHistory() {
+  localStorage.setItem(HISTORY_STORAGE_KEY, JSON.stringify(viewHistory.value))
+}
+
+loadHistory()
+
+export function useViewHistory() {
+  function addToHistory(entry: Omit<HistoryEntry, 'viewedAt'>) {
+    // Remove duplicate
+    viewHistory.value = viewHistory.value.filter(h => h.id !== entry.id)
+    // Add to front
+    viewHistory.value.unshift({ ...entry, viewedAt: Date.now() })
+    // Cap at MAX_HISTORY
+    if (viewHistory.value.length > MAX_HISTORY) {
+      viewHistory.value = viewHistory.value.slice(0, MAX_HISTORY)
+    }
+    saveHistory()
+  }
+
+  function clearHistory() {
+    viewHistory.value = []
+    saveHistory()
+  }
+
+  return {
+    viewHistory,
+    addToHistory,
+    clearHistory,
+  }
+}
+
+// M13.7 — Trending in conversations
+const REFERENCE_STORAGE_KEY = 'aiui-content-references'
+
+interface ReferenceEntry {
+  id: string
+  title: string
+  type: FavoriteType
+  count: number
+  lastReferenced: number
+}
+
+const trendingItems = ref<ReferenceEntry[]>([])
+
+function loadReferences() {
+  try {
+    const stored = localStorage.getItem(REFERENCE_STORAGE_KEY)
+    if (stored) trendingItems.value = JSON.parse(stored)
+  } catch { /* ignore */ }
+}
+
+function saveReferences() {
+  localStorage.setItem(REFERENCE_STORAGE_KEY, JSON.stringify(trendingItems.value))
+}
+
+loadReferences()
+
+export function useTrending() {
+  function recordReference(item: { id: string; title: string; type: FavoriteType }) {
+    const existing = trendingItems.value.find(t => t.id === item.id)
+    if (existing) {
+      existing.count++
+      existing.lastReferenced = Date.now()
+    } else {
+      trendingItems.value.push({
+        id: item.id,
+        title: item.title,
+        type: item.type,
+        count: 1,
+        lastReferenced: Date.now(),
+      })
+    }
+    saveReferences()
+  }
+
+  const trending = computed(() => {
+    const thirtyDaysAgo = Date.now() - 30 * 86400 * 1000
+    return trendingItems.value
+      .filter(t => t.lastReferenced > thirtyDaysAgo)
+      .sort((a, b) => b.count - a.count)
+      .slice(0, 20)
+  })
+
+  return {
+    trending,
+    recordReference,
+  }
+}
diff --git a/packages/app/src/composables/useSimilarContent.ts b/packages/app/src/composables/useSimilarContent.ts
new file mode 100644
index 00000000..be894b41
--- /dev/null
+++ b/packages/app/src/composables/useSimilarContent.ts
@@ -0,0 +1,105 @@
+import { ref } from 'vue'
+import type { FavoriteType } from '@/stores/favorites'
+import { getApiKey } from '@/utils/key-vault'
+
+const CACHE_KEY = 'aiui-similar-content'
+const CACHE_DURATION = 7 * 24 * 60 * 60 * 1000 // 7 days
+
+interface SimilarItem {
+  title: string
+  type: FavoriteType
+  reason: string
+}
+
+interface CachedSuggestion {
+  itemId: string
+  suggestions: SimilarItem[]
+  cachedAt: number
+}
+
+function loadCache(): CachedSuggestion[] {
+  try {
+    const stored = localStorage.getItem(CACHE_KEY)
+    if (stored) return JSON.parse(stored)
+  } catch { /* ignore */ }
+  return []
+}
+
+function saveCache(cache: CachedSuggestion[]) {
+  localStorage.setItem(CACHE_KEY, JSON.stringify(cache))
+}
+
+export function useSimilarContent() {
+  const suggestions = ref<SimilarItem[]>([])
+  const isLoading = ref(false)
+
+  async function fetchSimilar(itemId: string, title: string, type: FavoriteType) {
+    // Check cache first
+    const cache = loadCache()
+    const now = Date.now()
+    const cached = cache.find(c => c.itemId === itemId && (now - c.cachedAt) < CACHE_DURATION)
+    if (cached) {
+      suggestions.value = cached.suggestions
+      return
+    }
+
+    isLoading.value = true
+    suggestions.value = []
+
+    try {
+      const apiKey = await getApiKey('claude')
+      if (!apiKey) {
+        isLoading.value = false
+        return
+      }
+
+      const typeLabel = type === 'tv' ? 'TV series' : type
+      const prompt = `List exactly 3 ${typeLabel}s similar to "${title}". For each, respond with ONLY a JSON array like: [{"title":"Name","reason":"one sentence why"}]. No other text.`
+
+      const res = await fetch('/api/claude/v1/messages', {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/json', 'x-api-key': apiKey },
+        body: JSON.stringify({
+          model: 'claude-haiku-4-5-20251001',
+          max_tokens: 300,
+          messages: [{ role: 'user', content: prompt }],
+        }),
+      })
+
+      if (!res.ok) {
+        isLoading.value = false
+        return
+      }
+
+      const data = await res.json()
+      const text = data.content?.[0]?.text ?? ''
+
+      // Extract JSON array from response
+      const match = text.match(/\[[\s\S]*\]/)
+      if (match) {
+        const parsed = JSON.parse(match[0]) as { title: string; reason: string }[]
+        const items: SimilarItem[] = parsed.slice(0, 3).map(p => ({
+          title: p.title,
+          type,
+          reason: p.reason,
+        }))
+        suggestions.value = items
+
+        // Cache result
+        const updatedCache = cache.filter(c => c.itemId !== itemId)
+        updatedCache.push({ itemId, suggestions: items, cachedAt: now })
+        // Keep cache small
+        if (updatedCache.length > 100) updatedCache.splice(0, updatedCache.length - 100)
+        saveCache(updatedCache)
+      }
+    } catch { /* ignore errors */ } finally {
+      isLoading.value = false
+    }
+  }
+
+  return {
+    suggestions,
+    isLoading,
+    fetchSimilar,
+  }
+}
diff --git a/packages/app/src/pages/ChatPage.vue b/packages/app/src/pages/ChatPage.vue
index 60ab8ddb..fd186be7 100644
--- a/packages/app/src/pages/ChatPage.vue
+++ b/packages/app/src/pages/ChatPage.vue
@@ -571,6 +571,7 @@ const TAB_LABELS: Record<ContentTab, string> = {
   'design-system': 'Design',
   nostr: 'Nostr',
   favorites: 'Favorites',
+  discover: 'Discover',
 }
 
 function tabLabel(tab: ContentTab): string {