I kind of modded my GBA a while back, and bought some upgrades like a better display and an sdcard using cartridge.

Now it's my travel device when I'm on holiday or having no energy left to focus on code. It's pretty convenient only because of the sdcard cartridge adapter.

Did not regret spending 50 bucks for the mods. Would heavily recommend.

[1] https://cookie.engineer/projects/hardware/gameboy-advance.ht...

Great write up, thank you. Actually I've been messing around with ARM assembly lately so have been keeping my eyes open for a cheap used GBA. There are a lot of them here, but most are close to 100usd and in really rough shape. So your link may come in handy someday :)