So far from what I've experienced now and what I'm using now is the Electrum apps in the Play Store. If you have an Electrum account in the desktop apps, you can still access the Play Store using your mobile device as long as the seed phrase is saved, or you know there is a chance that you can also open it in the Electrum apps on Android.
I am having a really hard time understanding all you said here, do you mean you downloaded Electrum from playstore, take note that you should only download Electrum through their official website and then verify your download before use.
The Trustwallet is also possible, as long as the amount of bitcoin is not too large, because, like others, larger amounts are recommended to be kept in the hardware wallet.
It isn't recommended to store any amount of your coins in Trust wallet, it is a closed source wallet and you cannot verify its code. If you want to store a small amount of coins in an online wallet, use Electrum, then if you want cold storage, run Electrum in an airgapped machine or buy a hardware wallet.