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kotlinlang

I am a beginner, so which platform is better for android development
a) IntelliJ  IDEA
b) Android Studio

android studio is usually better for beginners I'd say since it has all the goodies preinstalled -- if you want to go with intellij you can install most of the same things, it'll just take some work

at what level of development, a beginner feels the real difference?

if there's something you really want from intellij it has more of the new IDE features, but otherwise I'd say go with android studio -- it'll get the same features, just a little later

though this is all based on what I've heard, I used intellij for android development just so I could use Junie the jetbrains AI agent -- but now I'm back to android studio

For a beginner aiming to learn android specifically, start with Android Studio because that is what all the tutorials you watch and documentation you read will be using.