Im confused

[Crypt00]

So I want my screen to time out when I have a specific app open because it has a permission on it where I won't let my phone sleep, if I forget it's open or fall asleep I run the risk of severe screen burn-in. So how do I set something like that on there?

 

[tanutanu]

So I want my screen to time out when I have a specific app open because it has a permission on it where I won't let my phone sleep, if I forget it's open or fall asleep I run the risk of severe screen burn-in. So how do I set something like that on there?

There are so many way to prevent the device from running out the battery while unexpected asleep.
If I were you, consider a vendor customized OS builtinfeature, power on/off, first. If with MD, checking the foreground app every an hour, and push the app in the background, then override the screen timeout like this.