I use https://play.google.com/store/apps/details?id=com.qqlabs.min... which has several things that pester you when opening certain applications. It also makes the home screen quite dull. Combine this with a monochrome display and the phone considerably loosens its grip on you.
I think it will work just fine in combination with Intenty. Of course, it might be too challenging to use the device with so many obstacles. But if that helps to be more mindful about phone usage, why not?