Hi,
Which things can I do with an old android phone ? Like a Xiaomi mi a3.
Next time you upgrade your phone you should try to do a trade in, it bumps some money off of the price and solves the issue of having an old phone laying around. Pretty sure they recycle the parts after that, so win-win.
When the phone (or whatever) is still usable I always prefer to sell it. You usually get more money and the usable product gets used some more instead of getting destroyed.
That’s essentially what a trade in is
I meant selled it on craigslist or something.
I use an old Nexus 5 I have as a offline GPS device for cycling.
Take the battery out of it. Put on lineage OS. Use it as a microserver, mine some crypto like monero. Because it’s CPU-based. You could use it as a remote for other devices. You could use it as a webcam for your house. It can do everything it used to do.
Old lithium batteries become a fire hazard, so I would recommend removing it if you can. Or at least replacing it with the new battery. Good practice at least even if you break it
Leaving an airplane mode, don’t use the cellular modem, you’re not getting any hardware driver updates. So it’s security risk. Don’t do anything too sensitive with it. But just for you around home network it’s fine