What can you do, when build is successful, but app does not work?

Hi everyone!

I made a minimal application, which is using firebase/storage and redux, it supposed to download some images from storage and just show them next to one another on two different tabs, but for testing I am using images from a fixed assets folder. I tested it in browser, ran on expo go on two different android devices (galaxy s5 and galaxy s9+), they have no errors, when running locally. I have built an apk with eas, it has an awful long log, with some [stderr] messages about deprecations here and there, but altogether all sections of the build are marked with the green check, it is successful in the end, however when I install it on the devices from the apk, then launch it, it shows the splash image for a second, and then ends up in a white screen, doing nothing. Where to begin debugging something like this?

I am a rookie in this, first build with expo ever.