if this is the same scientifically proven 7 minute work out that was making the rounds a few months ago it's results were based on basically going hard enough to make yourself puke for the whole 7 minutes.

If you're not doing it at sufficient intensity it is probably fairly pointless.

Effective at what though?

The problem with these one-size-fits-all "exercise for N minutes" memes is that every person has different goals for what they want to get out of exercise.

I’ll give it a shot, why not?

Why does it need to be an app? Why not a piece of paper tacked to the wall?