In some cases you can crack them open and do things. I'm guessing there are similar options for your Android phone. Of the 4 iPhones of various gens we've had in our house, only one had issues, due to rough treatment and the battery going bad. So we ordered parts and Mr. TS swapped out the battery and back plate himself without much hassle.

I managed to break one of the USB ports in my MacBook. (dropped it on the port side with something plugged in) To fix it, I have the option of replacing the logic board myself.

They're not as modular as a PC, but it's not like they're magically sealed up devices with no way to work on them.