powersave options (screen off) for activity apps?

Hi,

For activity apps, Is it possible to utilize a screen off/on on hand movement as is built in with watch faces? 

I have an activity app (super app) that runs over long period of times and it's rather power hungry. I noticed that the (AMOLED) screen goes into lower brightness when inactive but it never swithces of entirely, like with watch faces. It would be great if this feature could be used for activity apps as well. Any ideas? 

/Fredrik