diff --git a/scripts/metrics-snapshot.ts b/scripts/metrics-snapshot.ts
index 3cbb7ff..2596e4c 100644
--- a/scripts/metrics-snapshot.ts
+++ b/scripts/metrics-snapshot.ts
@@ -84,6 +84,12 @@ if (process.env.STATS_KEY) {
       for (const g of stats.active_by_source_platform || []) {
         addRow('subscribers_active', `${g.source}/${g.platform || 'none'}`, g.count);
       }
+      // Daily active installs via updater check-ins (#111 Phase 2). Only the
+      // last 7 days — weekly runs overlap, dedupe on (date, metric, label).
+      for (const d of (stats.updater_checkins_by_day || []).slice(0, 7)) {
+        addRow('updater_uniques', d.day, d.uniques);
+        addRow('updater_checkins', d.day, d.total);
+      }
     } else {
       console.warn(`[metrics] stats endpoint -> ${res.status} (skipping subscriber counts)`);
     }
diff --git a/src-tauri/tauri.conf.json b/src-tauri/tauri.conf.json
index e615814..c23cb32 100644
--- a/src-tauri/tauri.conf.json
+++ b/src-tauri/tauri.conf.json
@@ -46,6 +46,7 @@
     },
     "updater": {
       "endpoints": [
+        "https://pullread.com/api/updater/latest.json",
         "https://github.com/shellen/pullread/releases/latest/download/latest.json"
       ],
       "pubkey": "dW50cnVzdGVkIGNvbW1lbnQ6IG1pbmlzaWduIHB1YmxpYyBrZXk6IDZBNDM3MTJBMEE5OUQwNEEKUldSSzBKa0tLbkZEYW5UUFRoc1gwSnlVMk5JaUIrMHBYL0pRblBkR1lLaWd3bkRxRFJjNjlDMk8K"
diff --git a/worker/src/index.ts b/worker/src/index.ts
index 58163da..ae1573f 100644
--- a/worker/src/index.ts
+++ b/worker/src/index.ts
@@ -147,6 +147,37 @@ async function handleExport(request: Request, env: Env): Promise<Response> {
   });
 }
 
+// ── Updater check-ins (#111 Phase 2) ─────────────────────
+// The app's updater fetches latest.json through this endpoint, giving a
+// daily active-install count without telemetry: one row per (day, salted
+// IP hash), then a redirect to the real manifest on GitHub. No user agent,
+// no version, no raw IP is stored.
+
+const UPDATER_MANIFEST_URL =
+  'https://github.com/shellen/pullread/releases/latest/download/latest.json';
+
+const CHECKINS_SCHEMA =
+  'CREATE TABLE IF NOT EXISTS updater_checkins (' +
+  'day TEXT NOT NULL, ip_hash TEXT NOT NULL, count INTEGER NOT NULL DEFAULT 1, ' +
+  'PRIMARY KEY (day, ip_hash))';
+
+async function handleUpdaterManifest(request: Request, env: Env): Promise<Response> {
+  // Counting must never block updates — redirect even if D1 hiccups.
+  try {
+    await env.DB.exec(CHECKINS_SCHEMA);
+    const day = new Date().toISOString().slice(0, 10);
+    const ip = request.headers.get('cf-connecting-ip') || 'unknown';
+    const ipHash = (await hmacHex(env.HMAC_SECRET, `checkin:${ip}`)).slice(0, 32);
+    await env.DB.prepare(
+      'INSERT INTO updater_checkins (day, ip_hash) VALUES (?, ?) ' +
+      'ON CONFLICT(day, ip_hash) DO UPDATE SET count = count + 1',
+    ).bind(day, ipHash).run();
+  } catch {
+    // swallow — the redirect below is the contract
+  }
+  return Response.redirect(UPDATER_MANIFEST_URL, 302);
+}
+
 async function handleStats(request: Request, env: Env): Promise<Response> {
   const url = new URL(request.url);
   if (url.searchParams.get('key') !== env.ADMIN_KEY) {
@@ -165,11 +196,22 @@ async function handleStats(request: Request, env: Env): Promise<Response> {
     "SELECT strftime('%Y-%W', created_at) AS week, source, COUNT(*) AS count FROM subscribers GROUP BY week, source ORDER BY week",
   ).all();
 
+  // Updater check-ins: uniques = distinct installs seen that day (#111)
+  let checkins: unknown[] = [];
+  try {
+    await env.DB.exec(CHECKINS_SCHEMA);
+    const rows = await env.DB.prepare(
+      'SELECT day, COUNT(*) AS uniques, SUM(count) AS total FROM updater_checkins GROUP BY day ORDER BY day DESC LIMIT 30',
+    ).all();
+    checkins = rows.results;
+  } catch { /* table empty/unavailable — report nothing rather than fail stats */ }
+
   return new Response(
     JSON.stringify({
       totals: { total: totals?.total ?? 0, active: totals?.active ?? 0 },
       active_by_source_platform: bySourcePlatform.results,
       signups_by_week: byWeek.results,
+      updater_checkins_by_day: checkins,
     }),
     { headers: { 'Content-Type': 'application/json' } },
   );
@@ -199,6 +241,10 @@ export default {
       return handleStats(request, env);
     }
 
+    if (url.pathname === '/api/updater/latest.json') {
+      return handleUpdaterManifest(request, env);
+    }
+
     return new Response('Not found', { status: 404 });
   },
 } satisfies ExportedHandler<Env>;
diff --git a/worker/test/index.test.ts b/worker/test/index.test.ts
index 5114def..4551d73 100644
--- a/worker/test/index.test.ts
+++ b/worker/test/index.test.ts
@@ -280,3 +280,47 @@ describe('GET /api/stats', () => {
     expect(res.status).toBe(403);
   });
 });
+
+// ── GET /api/updater/latest.json ─────────────────────────
+
+describe('GET /api/updater/latest.json', () => {
+  test('redirects to the GitHub manifest and records a check-in', async () => {
+    const res = await SELF.fetch('https://fake.host/api/updater/latest.json', {
+      headers: { 'cf-connecting-ip': '203.0.113.7' },
+      redirect: 'manual',
+    });
+    expect(res.status).toBe(302);
+    expect(res.headers.get('Location')).toBe(
+      'https://github.com/shellen/pullread/releases/latest/download/latest.json',
+    );
+
+    const rows = await env.DB.prepare('SELECT day, ip_hash, count FROM updater_checkins').all();
+    expect(rows.results.length).toBe(1);
+    expect(rows.results[0].count).toBe(1);
+    // Raw IP never stored — only a salted hash
+    expect(String(rows.results[0].ip_hash)).not.toContain('203.0.113.7');
+  });
+
+  test('same IP same day increments count, not uniques; new IP adds a row', async () => {
+    const opts = (ip: string) => ({ headers: { 'cf-connecting-ip': ip }, redirect: 'manual' as const });
+    await SELF.fetch('https://fake.host/api/updater/latest.json', opts('203.0.113.7'));
+    await SELF.fetch('https://fake.host/api/updater/latest.json', opts('203.0.113.7'));
+    await SELF.fetch('https://fake.host/api/updater/latest.json', opts('198.51.100.9'));
+
+    const rows = await env.DB.prepare(
+      'SELECT COUNT(*) AS uniques, SUM(count) AS total FROM updater_checkins',
+    ).first();
+    expect(rows.uniques).toBe(2);
+    expect(rows.total).toBe(3);
+  });
+
+  test('stats endpoint reports check-ins by day', async () => {
+    await SELF.fetch('https://fake.host/api/updater/latest.json', {
+      headers: { 'cf-connecting-ip': '203.0.113.7' }, redirect: 'manual',
+    });
+    const res = await SELF.fetch('https://fake.host/api/stats?key=test-admin-key');
+    const body = await res.json();
+    expect(body.updater_checkins_by_day.length).toBe(1);
+    expect(body.updater_checkins_by_day[0].uniques).toBe(1);
+  });
+});