I wouldn't exactly call that secure disposal. Yes, the factory reset is the bare minimum. But you can probably still recover data off of it. To really be secure

I wouldn't exactly call that secure disposal. Yes, the factory reset is the bare minimum. But you can probably still recover data off of it. To really be secure you have to run a wipe on the memory and storage. I would be interested in articles covering how to do that for phones and IoT devices. It's trivial to do on a computer, but much harder on other devices.