My final advice for all smartphone users is that the less apps you install on your phone the better, the less likely you are exposed to data leaking apps or malicious app, and don't use any app store to install apps, directly find their official website, that should direct you to the right apps on stores or direct download.
Do people still use crypto wallet that allows taking screenshot? I don't know for others but right from setting up a wallet, if I discover that it allows taking screenshot of keys phrases, I will instantly discard it without a second thought because it is a sign of weak security protocol from the developers. On the aspect of keyboard, I don't know what third party keyboards offer that phone built in keyboard doesn't offer which makes people to use them despite knowing the risk involved nowadays. I remember back then when I used third party keyboard but whenever I enter any site or app that requires typing of password or other sensitive information, my phone will automatically switch to phone built in keyboard. That's how things are supposed to be but I don't know what's wrong this days. Some of these security threats can be avoided by us using simple measures but we choose to overlooked it until it causes harm.