Disable all blackground apps when using some apps (possibly with Tasker) Is there a way to disable all background apps (gmail, google notifications, messaging apps, etc...) when a certain/any app is running? I would like to do this because I play a certain game (Sine Line) which requires you to press the screen for short periods of time, in a very controlled manner, and any lag kills me.

I assume this could be useful for other resource-intensive apps, such as maps/gps, or image editing.

Either disabling/killing background apps when a certain or any app is running are acceptable solutions. Tasker is also acceptable, however Tasker itself is quite resource-intensive so avoiding it would be best.

Thanks
You can do so by forcing the system to limite background processes. Open the Settings > Developers Options > Limite background processes and select No background process. 

If Developers Options is not enabled (on Android 4.4.2 and above), enable it at Settings > About phone > Tape 7 times on Build number > Go back to Settings, the option should be on.