1. 8 GB RAM is going to be very tight, especially if you want to run Android Studio and Xcode and a simulator side by side. I’ve been using 32 GB for a couple of years now, but 16 GB will probably be fine.
2. M2 is a bit faster than M1. A much bigger difference will be M1/M2 vs. M1/M2 Pro though, if you buy one with a 10 or 12 core CPU. Compiling code can use a lot of cores in parallel. Note that the base-level MacBook Pro doesn’t have a Pro CPU, and that the Max CPUs are a waste of money if you’re not after the additional *G*PU power. Their CPU part is the same as in the Pro chips. There are
benchmarks for all the machines available. Just switch to the multi-core tab and compare the candidate models.
3. Depends a lot on how much money you want to spend. The minimum I would buy would be a MacBook Air with 16 GB of RAM. You’ll get a considerable upgrade in terms of speed if you get a MacBook Pro with a 10 or 12 core M1/M2 Pro CPU. MBPs also can use their full CPU power for longer than MBAs because they have a fan to keep the CPU cool (not that you’ll notice most of the time, it’s really quiet and even off most of the time). And you should think about whether the base-level SSD with only 256 GB will be sufficient for you, especially when you notice what an amazing (just a bit pricey) machine you just bought and you want to use it more than just occasionally 🙃