Shelter - Isolate your Big Brother Apps
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.
DU Battery Saver - DU Battery Saver, get up to 50% more battery life for your Android phone. Battery Saver learns how you use your phone, then creates smart profiles that match your settings to your needs while getting more life from your battery.