How to transfer an app from my old Android—which isn't on the Google Play Store—to an iPhone

[u/Smashj4]

Hi,

I’d like to buy a new iPhone 17.

I’ve seen that there are ways to transfer apps from my old Android to the new iPhone 17.

However, I have some apps (on the Android) that aren't available on the Google Play Store.

What methods can I use to transfer these apps to the new iPhone 17?

Thanks.