Please have a look at this app. What does this app use to figure out a device&log in?

I have a sh!tty University attendance check app that needs manual confirmation from head office that takes 2 days every time I chang my device. However, this app thinks that I have changed my device even when I flash a new ROM or factory reset my phone.

So far, I requested 20 times and the office headmaster doesn't seem to like it

So I am wondering, how does this app figure out that I've "changed" my device?
I've tried to use Titanium backup but it doesn't work.
So far, the only way I can backup is to backup 'data' partition in twrp and restore it in another rom. But as you know, that is not practical when you jump between LOS base ROMs and AOSP based ROMs...

I am not knowledgeable in dissecting apps and figuring out how this works, so I need some help from you.

The app is this :

(I'll upload the apk file later if you have problems downloading for play store in your area)

Can someone good at app developing have a look at this and figure out what this app uses to check my device and log in?
Or if you have any idea what this app uses to figure out a device, please tell me. Any help will be appreciated!

Show Accepted Answer

Guest Quick Reply (No URL, BBcode or HTML)

Last post by olen.bogan
3 hours ago
Last post by nwhite
1 hour ago
Last post by zschulist
1 hour ago
Last post by vicenta.wunsch
2 hours ago
Last post by ejacobi
1 hour ago
Last post by domingo.rippin
3 hours ago
Last post by ebert.emilio
3 hours ago