Imgflip

There's already an app bro. Look.
Android: https://play.google.com/store/apps/details?id=com.imgflip.twa
iOS: You have to add it in the home screen.
Here's the instructions:
imgflip.com/i/4gl615
For information about the app "Slack API", go to this link.
https://github.com/rusito-23/Meme-Generator-iOS

i don't think it's possible to do so and it's impossible to add apks onto apple products