How do you suggest code review feedback where you think there’s a better way to do what they’re currently doing?

• Focus on asking good questions. Point out what you find confusing and why.
• When starting out, I’d recommend actually applying a code change and running it in your local environment. Try to reproduce their test plan and check how it can be improved.
• Another way to become an effective code reviewer is to suggest additional ways to test the code.
• Start from your base of knowledge, e.g. how was this done on Android, and fill in the context.

First thing's first: The entire point of code review is to try to level up the code quality, either directly (e.g. "We can write this method in this better way.") or indirectly (e.g. "I think we can establish this best practice on the team to improve future code quality."). So don't feel bad about pointing out that you think a peer's code can be better in core review - That's the entire point!

The main things around leaving code review feedback is to be kind and empathetic. Use tentative language always and criticize the code, not the person. You're probably already doing that, since you haven't gotten any negative feedback on your code review so far.

For folks who haven't seen it yet, here's the in-depth session we did about code review best practices.