diff --git a/.gitea/workflows/ci.yml b/.gitea/workflows/ci.yml
index ddad224..9aa87a3 100644
--- a/.gitea/workflows/ci.yml
+++ b/.gitea/workflows/ci.yml
@@ -7,12 +7,12 @@
 # `docker compose` simply builds and (re)creates the `wisp` container on the host.
 #
 # Triggers:
-#   push to master -> test, then deploy-web
+#   push to master -> test, then deploy-web, then build-apk
 #   pull_request   -> test only
 #
-# Required repo secrets (Settings -> Actions -> Secrets) — used by the APK job
-# once it is enabled (see TODO at the bottom): ANDROID_KEYSTORE_BASE64,
-# ANDROID_KEYSTORE_PASSWORD, ANDROID_KEY_ALIAS, ANDROID_KEY_PASSWORD.
+# Required repo secrets (Settings -> Actions -> Secrets) — used by the build-apk
+# job: ANDROID_KEYSTORE_BASE64, ANDROID_KEYSTORE_PASSWORD, ANDROID_KEY_ALIAS,
+# ANDROID_KEY_PASSWORD.
 # ---------------------------------------------------------------------------
 
 name: CI
@@ -72,11 +72,11 @@ jobs:
   # with docker create/cp and copy it into the running `wisp` web container so
   # it is downloadable at https://wisp.briggen.dev/wisp.apk.
   build-apk:
-    # ONLY on version tags (v*). The native build is heavy (NDK/whisper.cpp) and
-    # slow on the shared prod runner; building it on every push would peg the box
-    # (and degrade the live web apps). Cut a release with: git tag v1.2.3 && git push --tags
-    needs: [test]
-    if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags/v')
+    # Auto-build the APK on every push to master (arm64-only keeps it ~minutes).
+    # Runs after deploy-web so the web updates promptly, then the APK follows and
+    # is published to /srv/wisp/wisp.apk (served at /wisp.apk via the compose mount).
+    needs: [test, deploy-web]
+    if: github.event_name == 'push' && github.ref == 'refs/heads/master'
     runs-on: ubuntu-latest
     timeout-minutes: 120
     steps:
diff --git a/src/app/(tabs)/_layout.tsx b/src/app/(tabs)/_layout.tsx
new file mode 100644
index 0000000..baac9c8
--- /dev/null
+++ b/src/app/(tabs)/_layout.tsx
@@ -0,0 +1,51 @@
+// Bottom tab navigation for the primary destinations (mobile-first). Secondary
+// screens (Record, Transcript, Courses, Quiz, Bibliography) are pushed on the
+// root Stack from within these tabs. Route-group parens keep URLs unchanged
+// (/, /search, /study, /ask, /settings).
+import { Tabs } from 'expo-router';
+import { Text, type ColorValue } from 'react-native';
+
+import { useTheme } from '@/hooks/use-theme';
+
+const ACCENT = '#3c87f7';
+
+function TabIcon({ glyph, color }: { glyph: string; color: ColorValue }) {
+  return <Text style={{ fontSize: 20, color }}>{glyph}</Text>;
+}
+
+export default function TabsLayout() {
+  const theme = useTheme();
+  return (
+    <Tabs
+      screenOptions={{
+        tabBarActiveTintColor: ACCENT,
+        tabBarInactiveTintColor: theme.textSecondary,
+        tabBarStyle: { backgroundColor: theme.background, borderTopColor: theme.backgroundElement },
+        headerStyle: { backgroundColor: theme.background },
+        headerTitleStyle: { color: theme.text },
+        headerTintColor: theme.text,
+        headerShadowVisible: false,
+      }}>
+      <Tabs.Screen
+        name="index"
+        options={{ title: 'Wisp', tabBarLabel: 'Library', tabBarIcon: ({ color }) => <TabIcon glyph="📚" color={color} /> }}
+      />
+      <Tabs.Screen
+        name="search"
+        options={{ title: 'Search', tabBarIcon: ({ color }) => <TabIcon glyph="🔎" color={color} /> }}
+      />
+      <Tabs.Screen
+        name="study"
+        options={{ title: 'Study', tabBarIcon: ({ color }) => <TabIcon glyph="🎴" color={color} /> }}
+      />
+      <Tabs.Screen
+        name="ask"
+        options={{ title: 'Ask', tabBarIcon: ({ color }) => <TabIcon glyph="✨" color={color} /> }}
+      />
+      <Tabs.Screen
+        name="settings"
+        options={{ title: 'Settings', tabBarIcon: ({ color }) => <TabIcon glyph="⚙️" color={color} /> }}
+      />
+    </Tabs>
+  );
+}
diff --git a/src/app/ask.tsx b/src/app/(tabs)/ask.tsx
similarity index 98%
rename from src/app/ask.tsx
rename to src/app/(tabs)/ask.tsx
index cf18e5c..f0a67b5 100644
--- a/src/app/ask.tsx
+++ b/src/app/(tabs)/ask.tsx
@@ -1,4 +1,4 @@
-import { Stack, useFocusEffect, useRouter } from 'expo-router';
+import { useFocusEffect, useRouter } from 'expo-router';
 import { useCallback, useState } from 'react';
 import {
   ActivityIndicator,
@@ -81,7 +81,6 @@ export default function AskScreen() {
 
   return (
     <ThemedView style={styles.fill}>
-      <Stack.Screen options={{ title: 'Ask' }} />
       <ScrollView contentContainerStyle={styles.content} keyboardShouldPersistTaps="handled">
         <ThemedText type="small" themeColor="textSecondary">
           Ask a question and get an answer grounded in your lectures — every claim links back to the
diff --git a/src/app/index.tsx b/src/app/(tabs)/index.tsx
similarity index 69%
rename from src/app/index.tsx
rename to src/app/(tabs)/index.tsx
index 573d63c..04e39ef 100644
--- a/src/app/index.tsx
+++ b/src/app/(tabs)/index.tsx
@@ -14,13 +14,12 @@ import { ThemedText } from '@/components/themed-text';
 import { ThemedView } from '@/components/themed-view';
 import { MaxContentWidth, Spacing } from '@/constants/theme';
 import { useTheme } from '@/hooks/use-theme';
-import { getRepo, type TranscriptMeta } from '@/lib/db';
+import type { TranscriptMeta } from '@/lib/db';
 import { formatClock } from '@/lib/format';
-import { MODELS } from '@/lib/models/catalog';
 import { pickAudio, type PickedAudio } from '@/lib/pickAudio';
 import { useCourses } from '@/stores/coursesStore';
 import { useTranscribe } from '@/stores/transcribeStore';
-import { useTranscripts, type CourseFilter } from '@/stores/transcriptsStore';
+import { useTranscripts } from '@/stores/transcriptsStore';
 
 export default function LibraryScreen() {
   const theme = useTheme();
@@ -31,21 +30,11 @@ export default function LibraryScreen() {
   const refreshCourses = useCourses((s) => s.refresh);
   const job = useTranscribe();
   const [picked, setPicked] = useState<PickedAudio | null>(null);
-  const [dueCount, setDueCount] = useState(0);
 
   useFocusEffect(
     useCallback(() => {
       void refresh();
       void refreshCourses();
-      let alive = true;
-      void getRepo()
-        .flashcardCounts()
-        .then((c) => {
-          if (alive) setDueCount(c.due);
-        });
-      return () => {
-        alive = false;
-      };
     }, [refresh, refreshCourses]),
   );
 
@@ -54,7 +43,7 @@ export default function LibraryScreen() {
   const onNew = useCallback(async () => {
     if (busy) return;
     const p = await pickAudio();
-    if (p) setPicked(p); // opens the pre-capture sheet
+    if (p) setPicked(p);
   }, [busy]);
 
   const onStart = useCallback(
@@ -74,42 +63,15 @@ export default function LibraryScreen() {
   return (
     <ThemedView style={styles.fill}>
       <ScrollView contentContainerStyle={styles.content}>
-        <View style={styles.headerRow}>
-          <View style={styles.flex}>
-            <ThemedText type="subtitle">Wisp</ThemedText>
-            <ThemedText type="small" themeColor="textSecondary">
-              Private transcription — runs on your device, nothing uploaded.
-            </ThemedText>
-          </View>
-          <View style={styles.headerLinks}>
-            <Link href="/search" asChild>
-              <Pressable hitSlop={8}>
-                <ThemedText type="link" themeColor="textSecondary">Search</ThemedText>
-              </Pressable>
-            </Link>
-            <Link href="/ask" asChild>
-              <Pressable hitSlop={8}>
-                <ThemedText type="link" themeColor="textSecondary">Ask</ThemedText>
-              </Pressable>
-            </Link>
-            <Link href="/courses" asChild>
-              <Pressable hitSlop={8}>
-                <ThemedText type="link" themeColor="textSecondary">Courses</ThemedText>
-              </Pressable>
-            </Link>
-            <Link href="/study" asChild>
-              <Pressable hitSlop={8}>
-                <ThemedText type="link" themeColor="textSecondary">
-                  {dueCount > 0 ? `Study (${dueCount})` : 'Study'}
-                </ThemedText>
-              </Pressable>
-            </Link>
-            <Link href="/settings" asChild>
-              <Pressable hitSlop={8}>
-                <ThemedText type="link" themeColor="textSecondary">⚙ Settings</ThemedText>
-              </Pressable>
-            </Link>
-          </View>
+        <View style={styles.subHeader}>
+          <ThemedText type="small" themeColor="textSecondary" style={styles.flex}>
+            On your device — nothing uploaded.
+          </ThemedText>
+          <Link href="/courses" asChild>
+            <Pressable hitSlop={8}>
+              <ThemedText type="link" themeColor="textSecondary">Courses ›</ThemedText>
+            </Pressable>
+          </Link>
         </View>
 
         <View style={styles.captureRow}>
@@ -120,7 +82,7 @@ export default function LibraryScreen() {
                 styles.captureBtn,
                 { backgroundColor: '#e5484d', opacity: busy ? 0.5 : pressed ? 0.85 : 1 },
               ]}>
-              <ThemedText style={styles.newButtonText}>🎙 Record</ThemedText>
+              <ThemedText style={styles.captureText}>🎙 Record</ThemedText>
             </Pressable>
           </Link>
           <Pressable
@@ -130,7 +92,7 @@ export default function LibraryScreen() {
               styles.captureBtn,
               { backgroundColor: '#3c87f7', opacity: busy ? 0.5 : pressed ? 0.85 : 1 },
             ]}>
-            <ThemedText style={styles.newButtonText}>＋ Import file</ThemedText>
+            <ThemedText style={styles.captureText}>＋ Import</ThemedText>
           </Pressable>
         </View>
 
@@ -142,18 +104,20 @@ export default function LibraryScreen() {
           </ThemedView>
         )}
 
-        <ScrollView horizontal showsHorizontalScrollIndicator={false} contentContainerStyle={styles.filterBar}>
-          <FilterChip label="All" active={courseFilter === 'all'} onPress={() => void setCourseFilter('all')} />
-          <FilterChip label="Unsorted" active={courseFilter === null} onPress={() => void setCourseFilter(null)} />
-          {courses.map((c) => (
-            <FilterChip key={c.id} label={c.name} active={courseFilter === c.id} onPress={() => void setCourseFilter(c.id)} />
-          ))}
-        </ScrollView>
+        {courses.length > 0 && (
+          <ScrollView horizontal showsHorizontalScrollIndicator={false} contentContainerStyle={styles.filterBar}>
+            <FilterChip label="All" active={courseFilter === 'all'} onPress={() => void setCourseFilter('all')} />
+            <FilterChip label="Unsorted" active={courseFilter === null} onPress={() => void setCourseFilter(null)} />
+            {courses.map((c) => (
+              <FilterChip key={c.id} label={c.name} active={courseFilter === c.id} onPress={() => void setCourseFilter(c.id)} />
+            ))}
+          </ScrollView>
+        )}
 
         <TextInput
           value={query}
           onChangeText={(t) => void setQuery(t)}
-          placeholder="Search transcripts…"
+          placeholder="Filter by title…"
           placeholderTextColor={theme.textSecondary}
           style={[styles.search, { color: theme.text, backgroundColor: theme.backgroundElement }]}
         />
@@ -162,7 +126,7 @@ export default function LibraryScreen() {
           <ActivityIndicator style={styles.pad} />
         ) : items.length === 0 ? (
           <ThemedText type="small" themeColor="textSecondary" style={styles.pad}>
-            {query ? 'No matches.' : 'No transcripts here yet. Pick an audio or video file to begin.'}
+            {query ? 'No matches.' : 'No lectures yet. Record one or import an audio/video file to begin.'}
           </ThemedText>
         ) : (
           items.map((t) => (
@@ -245,9 +209,7 @@ function TranscriptRow({
     <Pressable onPress={onOpen} style={({ pressed }) => [pressed && styles.pressed]}>
       <ThemedView type="backgroundElement" style={styles.card}>
         <View style={styles.rowBetween}>
-          <ThemedText type="smallBold" numberOfLines={1} style={styles.flex}>
-            {item.title}
-          </ThemedText>
+          <ThemedText type="smallBold" numberOfLines={1} style={styles.flex}>{item.title}</ThemedText>
           <Pressable onPress={onDelete} hitSlop={8}>
             <ThemedText type="small" themeColor="textSecondary">✕</ThemedText>
           </Pressable>
@@ -269,20 +231,19 @@ const styles = StyleSheet.create({
     maxWidth: MaxContentWidth,
     width: '100%',
     alignSelf: 'center',
+    paddingBottom: Spacing.six,
   },
   flex: { flex: 1 },
-  headerRow: { flexDirection: 'row', alignItems: 'flex-start', gap: Spacing.two },
-  headerLinks: { flexDirection: 'row', gap: Spacing.three, alignItems: 'center' },
-  newButton: { paddingVertical: Spacing.three, borderRadius: Spacing.three, alignItems: 'center' },
-  newButtonText: { color: '#fff', fontWeight: '700', fontSize: 16 },
+  subHeader: { flexDirection: 'row', alignItems: 'center', gap: Spacing.two },
   captureRow: { flexDirection: 'row', gap: Spacing.two },
   captureBtn: { flex: 1, paddingVertical: Spacing.three, borderRadius: Spacing.three, alignItems: 'center' },
+  captureText: { color: '#fff', fontWeight: '700', fontSize: 16 },
   card: { padding: Spacing.three, borderRadius: Spacing.three, gap: Spacing.two },
   rowBetween: { flexDirection: 'row', alignItems: 'center', justifyContent: 'space-between', gap: Spacing.two },
   filterBar: { gap: Spacing.two, paddingVertical: Spacing.one, paddingRight: Spacing.three },
-  filterChip: { paddingHorizontal: Spacing.three, paddingVertical: Spacing.one, borderRadius: 999 },
+  filterChip: { paddingHorizontal: Spacing.three, paddingVertical: Spacing.two, borderRadius: 999 },
   chipActive: { color: '#fff', fontWeight: '700' },
-  search: { borderRadius: Spacing.two, paddingHorizontal: Spacing.three, paddingVertical: Spacing.two, fontSize: 15 },
+  search: { borderRadius: Spacing.two, paddingHorizontal: Spacing.three, paddingVertical: Spacing.three, fontSize: 15 },
   track: { height: 6, borderRadius: 3, backgroundColor: '#88888833', overflow: 'hidden' },
   bar: { height: 6, borderRadius: 3, backgroundColor: '#3c87f7' },
   pad: { paddingVertical: Spacing.four, textAlign: 'center' },
diff --git a/src/app/search.tsx b/src/app/(tabs)/search.tsx
similarity index 98%
rename from src/app/search.tsx
rename to src/app/(tabs)/search.tsx
index 808d139..ce8dd99 100644
--- a/src/app/search.tsx
+++ b/src/app/(tabs)/search.tsx
@@ -1,4 +1,4 @@
-import { Stack, useFocusEffect, useRouter } from 'expo-router';
+import { useFocusEffect, useRouter } from 'expo-router';
 import { useCallback, useEffect, useRef, useState } from 'react';
 import { ActivityIndicator, Pressable, ScrollView, StyleSheet, TextInput, View } from 'react-native';
 
@@ -104,7 +104,6 @@ export default function SearchScreen() {
 
   return (
     <ThemedView style={styles.fill}>
-      <Stack.Screen options={{ title: 'Search' }} />
       <ScrollView contentContainerStyle={styles.content} keyboardShouldPersistTaps="handled">
         <ThemedText type="small" themeColor="textSecondary">
           Semantic search across your lectures — runs entirely on your device.
diff --git a/src/app/settings.tsx b/src/app/(tabs)/settings.tsx
similarity index 100%
rename from src/app/settings.tsx
rename to src/app/(tabs)/settings.tsx
diff --git a/src/app/study.tsx b/src/app/(tabs)/study.tsx
similarity index 95%
rename from src/app/study.tsx
rename to src/app/(tabs)/study.tsx
index 14f9fc0..fbabd75 100644
--- a/src/app/study.tsx
+++ b/src/app/(tabs)/study.tsx
@@ -1,4 +1,4 @@
-import { Stack, useFocusEffect, useRouter } from 'expo-router';
+import { useFocusEffect, useRouter } from 'expo-router';
 import { useCallback, useState } from 'react';
 import { ActivityIndicator, Pressable, ScrollView, StyleSheet, View } from 'react-native';
 
@@ -80,17 +80,12 @@ export default function StudyScreen() {
 
   return (
     <ThemedView style={styles.fill}>
-      <Stack.Screen
-        options={{
-          title: 'Study',
-          headerRight: () => (
-            <Pressable onPress={() => void exportAnki()} hitSlop={8}>
-              <ThemedText type="link" themeColor="textSecondary">Export Anki (.csv)</ThemedText>
-            </Pressable>
-          ),
-        }}
-      />
       <ScrollView contentContainerStyle={styles.content}>
+        <View style={styles.topActions}>
+          <Pressable onPress={() => void exportAnki()} hitSlop={8}>
+            <ThemedText type="link" themeColor="textSecondary">Export Anki (.csv)</ThemedText>
+          </Pressable>
+        </View>
         <ScrollView horizontal showsHorizontalScrollIndicator={false} contentContainerStyle={styles.filterBar}>
           <FilterChip label="All" active={scope === 'all'} onPress={() => pickScope('all')} />
           <FilterChip label="Unsorted" active={scope === null} onPress={() => pickScope(null)} />
@@ -192,6 +187,7 @@ const styles = StyleSheet.create({
   },
   filterBar: { gap: Spacing.two, paddingVertical: Spacing.one, paddingRight: Spacing.three },
   filterChip: { paddingHorizontal: Spacing.three, paddingVertical: Spacing.one, borderRadius: 999 },
+  topActions: { flexDirection: 'row', justifyContent: 'flex-end' },
   chipActive: { color: '#fff', fontWeight: '700' },
   card: { padding: Spacing.four, borderRadius: Spacing.three, gap: Spacing.three },
   front: { fontSize: 24, lineHeight: 32 },
diff --git a/src/app/_layout.tsx b/src/app/_layout.tsx
index ba03e6c..fb20bb1 100644
--- a/src/app/_layout.tsx
+++ b/src/app/_layout.tsx
@@ -14,16 +14,12 @@ export default function RootLayout() {
   return (
     <ThemeProvider value={scheme === 'dark' ? DarkTheme : DefaultTheme}>
       <Stack>
-        <Stack.Screen name="index" options={{ title: 'Wisp' }} />
+        <Stack.Screen name="(tabs)" options={{ headerShown: false }} />
         <Stack.Screen name="record" options={{ title: 'Record' }} />
         <Stack.Screen name="transcript/[id]" options={{ title: 'Transcript' }} />
-        <Stack.Screen name="search" options={{ title: 'Search' }} />
-        <Stack.Screen name="ask" options={{ title: 'Ask' }} />
         <Stack.Screen name="courses" options={{ title: 'Courses' }} />
-        <Stack.Screen name="study" options={{ title: 'Study' }} />
         <Stack.Screen name="quiz" options={{ title: 'Quiz' }} />
         <Stack.Screen name="bibliography" options={{ title: 'Bibliography' }} />
-        <Stack.Screen name="settings" options={{ title: 'Settings' }} />
       </Stack>
       <StatusBar style="auto" />
     </ThemeProvider>