How can I customise my LG to make it old person compatible?

I just upgraded to an iphone and want to give my elderly mum a phone she can use to contact me with, she's always sick and I worry when we get seperated in public because she's prone to hypos and doesn't have a way to get a stranger to call my number on her behalf to let me know where she is so I can come and help her. I want to make my LG as old person friendly as possible but so far I can only think of max volume, not letting the screen time out, keeping brightness up at all times and making font bigger.