Keep Onyx Phone calls ringing on Samsung Galaxy phones

1. Unrestricted battery use

Optimized, the default, can hold back a call while the phone sits idle.

1. Open Settings, then Apps, then Onyx Phone.
2. Tap Battery and choose Unrestricted.

2. Never auto sleeping apps

Samsung puts apps it thinks you don't use to sleep, even with Unrestricted battery use, and may do it again after a software update.

1. Open Settings, then Battery, then Background usage limits (on older phones, Settings, then Battery and device care, then Battery, then Background usage limits).
2. Tap Never auto sleeping apps (Never sleeping apps on some phones), tap +, and add Onyx Phone.
3. Check that Onyx Phone isn't listed under Sleeping apps or Deep sleeping apps.

3. Keep its permissions

If Onyx Phone goes unopened for a few months, Android can take back its permissions, the microphone and notifications included.

1. Open Settings, then Apps, then Onyx Phone.
2. Turn off Remove permissions if app is unused.

4. Full-screen calls

Lets a call fill the screen when the phone is locked or you're using another app, like a regular call.

1. Open Onyx Phone. On the Calls tab, tap Allow on Show incoming calls full screen, and turn on what it opens.

Calls ring on mobile data but not on one Wi-Fi network

Calls reach the app through Google's push service, over one connection your phone keeps open for every app. Some Wi-Fi routers and office firewalls close a connection that has been quiet for a few minutes, and until the phone notices, a call can't reach it. Onyx Phone keeps that connection busy and sends a call again when your phone doesn't start ringing, which covers most networks.

• Set Onyx Phone's battery use to Unrestricted (above), so it can keep the connection busy.
• If one network still misses calls, ask whoever runs it to let quiet connections stay open for at least 15 minutes (often called the TCP or NAT timeout), and to allow outgoing connections on port 5228, which Google uses for push.

Check that it works

Leave the phone locked and untouched for 15 minutes, then have someone call your business number. It should wake the screen and ring. The Android setup guide covers the microphone, notifications, and the rest.