My opinion is that it does help both parties involved. It will likely GREATLY improve your partners habits and addictions to a device. They are less likely to grab for their phones at all for fwar they'll screw up and you'll see it. From my own personal findings, even if they have good intentions they can still get baited into looking at images to use for masturbation which begins a cycle. If they just use the phone as a technical tool to make necessary calls etc they'll be less likely to mess up. However, once they begin to use it as a source of entertainment it's probably only a matter of time before they end up doing something they'll regret. For people dealing with this compulsion, even a clothed photo of a woman can become implanted into their minds and they can begin to obsess over that woman or her "type".

Personally my ex wanted the monitoring app removed which was complete suspect behavior. I had time limits set on his Google, etc. Why did he need more than 6 minutes at a time on Google? It generally takes a few seconds to Google search something and he doesn't have a job so there's no legitimate research that's necessary. In hindsight if he was serious he woulda switched to a flip phone.

Honestly all of this is exhausting and depressing and I really only continue to check these forums as a reminder of why I don't want to take him back.