Finally following up from the archived thread:  https://www.ar15.com/forums/general/Mobile-Android-Parental-Controls-/75-2163214/

Been reading up on it online and see a lot of praise for Qustodio, but not much mention of MMGuardian.

Anybody used/have experience with both and can give an honest head to head comparison?

Mainly looking to set access times to keep them from being on it 24/7 (turn off both wifi and 4G on a schedule, or allow calls only within a specified time range, etc).

Monitoring texts/calls and location finding are also priorities.  Social media monitoring, etc would be nice too.

I've had MMGuardian on my 14 year old son's phone for the last year. I love it and he hates it.

You have individual control of every app. You can require them to use the MMGuardian texting app, and get an alert if they're sending or receiving texts with any words you choose. You can pick what browser they use and it can filter sites. You can also set the phone to lock or unlock at certain times of the day. His locks at 1030 PM every night and unlocks at 6 AM. I can send a text and lock or unlock it at any time. He can still emergency call and text when locked.

I've been very happy with it.