Tinycore

Tinycore is a lightweight app that monitors different metrics on your Android and displays them in your notifications bar or on any other part of the screen. To do so it has a bar icon to give you an idea of the percentage of memory available or how much of your CPU is being used.

The app lets you configure and customize the monitoring system, including the screen position and other settings like the shape or color of the bar. That said, some of the features – like, for example, the one to simultaneously show more than one setting on the screen at a time – are only available in the paid version of the app.

Tinycore is a lightweight tool that requires no special permissions to work. It displays more information than the Android interface offers on the home screen – and all without using too many resources, widgets, or other annoying stuff.