Enjoy the closest thing to a cold wallet on a phone imo.

Bonus: If you install a trusted VPN or Orbot in your main profile, you add it to the secondary user profile during install too. That way, you can set them up to connect and run as full-device VPN with the android setting to be "Always-on" + block all connections outside them. Once this is set up you can enable internet. Then it's obviously easier to send/receive transactions.

If you never want to be online every with this profile, note that connections are device-wide on Android so you can't be offline in the second user while on wifi with the main one.

And if you're never online with this profile, obviously that adds some hurdles to using the wallet to send/receive. Receive less-so, just generate a receive address and scan QR with a second phone or something.

What this does is it keeps your main user's connection separate from your secondary user. So you don't visit Facebook with the same IP as you're broadcasting a transaction or downloading bitcoin stuff in the second user if you're on the same WiFi.

Installing in main profile then adding to the second means you don't need to browse around installing or updating apps in the second profile. You do that from the main one even if you don't use the wallet or apps there. I think you can disable em and they'll still update (and be updated for the second user too).

use bluewallet in an old phone and keep it offline