True, but how is it possible to do that considering the fact that there are so many apps for airdrop and doing testnet these days. I literally do not even know the number of apps I have in my phone these days. Maybe, one needs to get a different phone for farming airdrops and testnet.
If you've so many apps installed on your phone, especially from unknown sources, there's a greater chance of getting your funds stolen by an hacker, as some of the apps may be developed and deployed on internet by scammers. My advice is that you get a hardware wallet for storing your funds offline while you use your phone for browsing and other activities.
The worse part of it is that any keyboard can get compromised with account synchronisation. So, the best thing is to use offline keyboards to avoid getting hacked or compromised with keyboad. I use my keyboard offline now.
I don't really get what you mean keyboard can be compromised by account synchronization. Also, I don't think there's any such thing as offline keyboard. To avoid losing your funds to scammers, do not install fancy or third party keyboard, only use the factory installed stock keyboard.