I was hired to be an Android developer for a startup. Other engineers on my team bounce around back-end, web iOS and Android. I make sure to review every Android PR that comes in but at the same time I have strived to review code from other projects like back-end and iOS. My primary language is Kotlin so I can offer advice on that but since others are written in typescript/Swift I am not sure how to offer reviews although I want to. I mostly end up asking questions.