Generally my way of figuring out what tech stack someone is using is to browse through their job offers. It's not a guarantee of course (I was hired as a rust developer at my old job only to be thrown into regurgitated spaghetti go). Anyhow, given that there's practically nothing related to native mobile development in the job offers (only one lists Java as a final mention), if I had to guess, my money would be a webvew app.
jatins
Whatever the stack is they need to change it. Love Claude on web, but it's unusable on Android app. _Always_ hangs mid generation, image upload corrupts images, swallows chats at will