diff --git a/docs/publish.md b/docs/publish.md
index 9ac600e9..355e99c1 100644
--- a/docs/publish.md
+++ b/docs/publish.md
@@ -492,6 +492,11 @@ You can set the priority with the header `X-Priority` (or any of its aliases: `P
   <figcaption>Detail view of priority notifications</figcaption>
 </figure>
 
+On **iOS**, max priority (`5`) messages are delivered as [critical alerts](https://developer.apple.com/documentation/usernotifications/unnotificationinterruptionlevel/critical),
+which break through silent mode and Do Not Disturb and play a sound at full volume. You must grant ntfy
+permission to send critical alerts (the app asks for it on first launch; it can also be toggled in
+**iOS Settings > Notifications > ntfy**).
+
 ## Tags & emojis 🥳 🎉
 _Supported on:_ :material-android: :material-apple: :material-firefox:
 
diff --git a/docs/releases.md b/docs/releases.md
index 5af903d7..a446ba81 100644
--- a/docs/releases.md
+++ b/docs/releases.md
@@ -1948,6 +1948,12 @@ and the [ntfy Android app](https://github.com/binwiederhier/ntfy-android/release
 
 ## Not released yet
 
+### ntfy server v2.25.0 (UNRELEASED)
+
+**Features:**
+
+* Send priority 5 (max/urgent) messages as iOS critical alerts (APNs critical sound + `interruption-level`), so they bypass silent mode and Do Not Disturb ([ntfy-ios#44](https://github.com/binwiederhier/ntfy-ios/pull/44), thanks to [@am7590](https://github.com/am7590) for the iOS app contribution)
+
 ### ntfy Android v1.25.x (UNRELEASED)
 
 This release makes the "connection lost" alert configurable and turns it off by default. Folks did not like it and many reached out
diff --git a/server/server_firebase.go b/server/server_firebase.go
index 0f1bb9b1..73c1f88e 100644
--- a/server/server_firebase.go
+++ b/server/server_firebase.go
@@ -241,16 +241,29 @@ func createAPNSAlertConfig(m *model.Message, data map[string]string) *messaging.
 	for k, v := range data {
 		apnsData[k] = v
 	}
+	aps := &messaging.Aps{
+		MutableContent: true,
+		Alert: &messaging.ApsAlert{
+			Title: m.Title,
+			Body:  maybeTruncateAPNSBodyMessage(m.Message),
+		},
+	}
+	headers := map[string]string{"apns-push-type": "alert"}
+
+	// Critical alerts (iOS): max priority messages bypass silent mode / Do Not Disturb. The iOS
+	// Notification Service Extension re-applies the critical sound based on priority, but we also
+	// flag the raw payload as critical (sound dict + interruption-level), so it stays critical even
+	// if the NSE never runs (e.g. when it exceeds its time budget or is dropped under memory pressure).
+	if m.Priority >= 5 {
+		aps.CriticalSound = &messaging.CriticalSound{Critical: true, Name: "default", Volume: 1.0}
+		aps.CustomData = map[string]any{"interruption-level": "critical"}
+		headers["apns-priority"] = "10"
+	}
 	return &messaging.APNSConfig{
+		Headers: headers,
 		Payload: &messaging.APNSPayload{
 			CustomData: apnsData,
-			Aps: &messaging.Aps{
-				MutableContent: true,
-				Alert: &messaging.ApsAlert{
-					Title: m.Title,
-					Body:  maybeTruncateAPNSBodyMessage(m.Message),
-				},
-			},
+			Aps:        aps,
 		},
 	}
 }
diff --git a/server/server_firebase_test.go b/server/server_firebase_test.go
index 40509fb9..1bd7526e 100644
--- a/server/server_firebase_test.go
+++ b/server/server_firebase_test.go
@@ -165,6 +165,9 @@ func TestToFirebaseMessage_Message_Normal_Allowed(t *testing.T) {
 		Priority: "high",
 	}, fbm.Android)
 	require.Equal(t, &messaging.APNSConfig{
+		Headers: map[string]string{
+			"apns-push-type": "alert",
+		},
 		Payload: &messaging.APNSPayload{
 			Aps: &messaging.Aps{
 				MutableContent: true,
@@ -248,6 +251,42 @@ func TestToFirebaseMessage_Message_Normal_Not_Allowed(t *testing.T) {
 	}, fbm.Data)
 	require.Equal(t, "", fbm.APNS.Payload.Aps.Alert.Title)
 	require.Equal(t, "New message", fbm.APNS.Payload.Aps.Alert.Body)
+	// Priority is kept when downgrading to a poll request (see toPollRequest), so a priority 5
+	// message still wakes iOS as a critical alert to poll for the message.
+	require.Equal(t, "10", fbm.APNS.Headers["apns-priority"])
+	require.True(t, fbm.APNS.Payload.Aps.CriticalSound.Critical)
+	require.Equal(t, "critical", fbm.APNS.Payload.Aps.CustomData["interruption-level"])
+}
+
+func TestToFirebaseMessage_Message_Critical(t *testing.T) {
+	m := model.NewDefaultMessage("mytopic", "this is urgent")
+	m.Priority = 5
+	m.Title = "wake up"
+	fbm, err := toFirebaseMessage(m, &testAuther{Allow: true})
+	require.Nil(t, err)
+
+	// Critical alerts use apns-priority 10, a critical sound dict, and interruption-level "critical"
+	// so the iOS device treats the message as critical (bypassing silent mode / Do Not Disturb).
+	require.Equal(t, "alert", fbm.APNS.Headers["apns-push-type"])
+	require.Equal(t, "10", fbm.APNS.Headers["apns-priority"])
+	require.NotNil(t, fbm.APNS.Payload.Aps.CriticalSound)
+	require.True(t, fbm.APNS.Payload.Aps.CriticalSound.Critical)
+	require.Equal(t, "default", fbm.APNS.Payload.Aps.CriticalSound.Name)
+	require.Equal(t, 1.0, fbm.APNS.Payload.Aps.CriticalSound.Volume)
+	require.Equal(t, "critical", fbm.APNS.Payload.Aps.CustomData["interruption-level"])
+}
+
+func TestToFirebaseMessage_Message_NotCritical(t *testing.T) {
+	m := model.NewDefaultMessage("mytopic", "this is normal")
+	m.Priority = 4
+	fbm, err := toFirebaseMessage(m, &testAuther{Allow: true})
+	require.Nil(t, err)
+
+	// Priority < 5 is a regular alert: no critical sound and no interruption-level.
+	require.Equal(t, "alert", fbm.APNS.Headers["apns-push-type"])
+	require.Empty(t, fbm.APNS.Headers["apns-priority"])
+	require.Nil(t, fbm.APNS.Payload.Aps.CriticalSound)
+	require.Nil(t, fbm.APNS.Payload.Aps.CustomData)
 }
 
 func TestToFirebaseMessage_PollRequest(t *testing.T) {
@@ -257,6 +296,9 @@ func TestToFirebaseMessage_PollRequest(t *testing.T) {
 	require.Equal(t, "mytopic", fbm.Topic)
 	require.Nil(t, fbm.Android)
 	require.Equal(t, &messaging.APNSConfig{
+		Headers: map[string]string{
+			"apns-push-type": "alert",
+		},
 		Payload: &messaging.APNSPayload{
 			Aps: &messaging.Aps{
 				MutableContent: true,