My 10 year old kid got a cell from his mom to use Wi-Fi, how do I make sure she doesn't use (or install in the future) monitoring apps?

I have a very controlling ex-wife. She once installed monitoring spyware on a PC when we were together. She hired a PI to follow me around. She constantly eavesdrop on my kids or spy on them while they are on the phone. She is an unemployed loser who spends 99% of her time online 'investigating' others.

She gave an Android phone to my 10 yo. No problem. I will reset it to factory settings so no worries there, but I …

apps future install monitoring old privacy wi-fi