Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
Accubattery - Monitor's battery capacity through the use of science
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
GSam Battery Monitor - Monitor your android devices battery usage.
Better Uptime - We call you when your website goes down
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.