Hi all! o/

I'm looking for an "air-gapped" wallet app for Android that could sign transactions on Sparrow. 

The plan is to install it on an old phone, open the phone and physically remove/disable de Wi-Fi/Bluetooth chips and then use this device to sign transactions on a multi sign Sparrow wallet.

I'm looking for something like nostr:npub1fgxdtgdunjresh5uzhnq0rrsjknnd5ejseegc7yntc2r7kg0k5xsfqc086 but without the need to source parts (yes, I live in the internet ghetto, AKA Brazil, and it's painful, expensive and a REALLY SLOW process to source the needed parts to build a seedsigner device).

Till now I gave a look on Electron, but couldn't make it work and I'm about to test Airgap Vault, although the idea of leaving the keys stored on a device does makes me feel uneasy and I'm still not sure if I will be able to make it work. 

Any other apps that you would recommend? =)