Not sure what it was called but you can get an app that completely locks selected items for android phones. You can log in as an adult and select what buttons, apps, messaging, etc the little ones can access and they are not able to restore default phone settings
Just found this
That looks very interesting, if only it didn't have a centralised tracking system! It'd be great if companies like Google, Apple and Blackberry could introduce such an app by default though.
I wonder how that app handles someone doing a full reset back to factory defaults.
O2 require age verification on internet traffic on all mobile devices connected through its network (not broadband), but only for what is classes as adult sites.
Safety, Control and Access - O2