Bluetooth not connecting?

This is the most common issue on the App Store reviews. The fix is almost always the same — and it works on both iOS and Android.

Quick checklist

1. Are both sock batteries actually on? Press the power button on each one and watch for the LED.
2. Is Bluetooth on at the phone level? Toggle it off and on once.
3. Is the app fully closed? Force-quit and reopen the WARMWORLD app — sometimes the scanner gets stuck.

The full reset sequence

If the quick checklist doesn't work, run this in order:

1. Forget the WARMWORLD device on the phone. iOS: Settings → Bluetooth, tap the i next to any WARMWORLD entry, Forget This Device. Android: Settings → Connections → Bluetooth → WARMWORLD → Unpair.
2. Power both batteries off (long-press until the LED goes out).
3. Toggle the phone's Bluetooth off, wait 10 seconds, toggle it back on.
4. Restart the WARMWORLD app. Quit it from the app switcher first.
5. Power both batteries back on (short press, LED on).
6. Open the app — the device picker should appear within five seconds.

If it still won't connect after that, try the same flow with a different phone. That tells you whether the issue is the phone's Bluetooth stack or the sock battery itself.