Blackout Curtain is a simple utility app. It has been created for reducing battery consumption by taking advantage of Multi-Window view in Android 7.0.

A smartphone with bigger screen means it contains more LED lights behind to light up the screen. Thus, bigger screen eats more battery, even though we can only focus on a part of the monitor.

While you are reading some articles, books etc., you can simply open and show Blackout Curtain on the half of the screen using Multi-Window function to reduce unnecessary battery consumption. Battery saving works well especially for devices using AMOLED technology, such as Samsung Galaxy series and Nexus 6/6P.