How can I show a custom In-App Message before the native iOS push permission prompt appears?

Yes. You can show a "pre-permission" or soft-prompt in-app message explaining the value of push notifications before the iOS system prompt appears. The key is to trigger the native permission prompt from a button inside your in-app message rather than calling the registration method at app launch.

Step-by-step guide

1. Create the in-app template. In the Control Panel go to Content → In-apps (Rich media) and create a template with the built-in editor, pick one from the built-in library, or upload your own ZIP.
2. Wire the button to the permission prompt. In the built-in editor, select the button (for example "Allow Notifications"), set Action type to Custom Javascript, and put this in the onClick field:

   window.pushwoosh.registerForPushNotifications()

   If you maintain the template as raw HTML instead, the same call goes in the button's onClick attribute:

   <button onclick="window.pushwoosh.registerForPushNotifications()">Enable Notifications</button>

   Replace any existing action such as window.pushwoosh.openAppSettings(). Use openAppSettings() only for users who have already denied permission, since iOS shows the system prompt only once.
3. Save the template.
4. Create the campaign. Go to Campaigns → Instant in-apps and click Create in-app.
5. Configure it: select your template, choose the audience, and pick the trigger event — for example the default PW_ApplicationOpen or PW_DeviceRegistered event, or a custom event fired after the user completes a meaningful action.
6. Save and launch. When the event fires the user sees your in-app first; tapping the button then shows the native iOS permission prompt.

Note: neither registerForPushNotifications() nor openAppSettings() closes the in-app message — they only forward the call to the SDK. Add window.pushwoosh.closeInApp() in the same onClick if you want the message to disappear after the tap.

Using this in a Customer Journey

The same in-app works inside a Customer Journey, but the timing differs:

• Instant in-apps are triggered immediately by an in-app event, so they display right away.
• Customer Journeys show the in-app immediately only if the app is open when the In-app element is reached; otherwise it is shown the next time the user opens the app.

For an opt-in flow specifically, the recommended pattern is a trigger-based Journey entered on PW_DeviceRegistered, or an Instant in-app as described above.