> How are people handling this these days?

Syncthing is wonderful, and does a great job of syncing between an Android phone's photos/videos and a laptop. And if you have regular automated backups of the laptop, you'll have backups of the photos/videos too.

For an iPhone, perhaps you could use iTunes to sync to a computer and back up that computer.

sushtrain seems like the best option for syncthing at the moment. its a bit more polished than mobius. neither of them sync in the background but i think i remember seeing someone using shortcuts to open the sushitrain app every now and again to wake it up so it would sync