Android Question Get or capture app running on top

[netsistemas]

How capture (with a service), the APP that are on top in device.
I want to do a service for capture the app that are using/viewing the user every 'x' seconds.

 

[lemonisdead]

This works for version before Android 5 : https://www.b4x.com/android/forum/threads/getting-a-list-of-running-apps.53682/
Since Lollipop it's deprecated