Personally, I use a thing called self-discipline.
If this app is actually legitimate, it shows at the very least that:
1) There is an incredibly serious lack of self-discipline in the world.
or
2) There is an incredibly powerful mind-altering ability in the technology.
or both.
We already know that multiple technologies are being used to "dumb-down" the population - to turn people into zombies - non-thinking people who live out their lives following along with the distractions created for them to occupy their time and thought. And today, there can be no doubt that "smart phones" are at the very center of it.
If this app is actually legitimate, and it helps people to learn to not live on their phone - then well and good; however, I am a bit skeptical - I see it as simply being "a new angle" to try to make money off of people and/through their personal weaknesses when the real solution to the real problem would not require such a method at all.
It is far better to establish good personal habits - based on what is internal.
When it comes to issues like this, "more technology" is rarely the answer...