Greenify - Greenify is a mobile app that gives you greater control over your Android device's power usage, allowing you to get a lot more mileage out of your battery life without having to constantly plug it back into a charger.

island - a free and opensource alternative to parellel space

SuperFreezZ - An Android app to completely stop all background activities of other apps.

App Cloner - Clone your Android apps so you can use multiple logins.

Brevent - 黑阈, Brevent

Parallel Space - Parallel Space – Multiple accounts and Two-Face is free to use mobile app that helps you clone or run multiple accounts of the same app simultaneously, and use themes to style your unique space.