DevInfoOverlay is a utility tool designed by Andrey Efremov for Android devices. It provides overlays that allow you to monitor your device's performance in real-time. The overlays display CPU frequency, RAM usage, battery level, voltage, charge and discharge speed, CPU load, and GPU load and frequency.

The app features style options such as transparency, text scaling, and colors (if you have a license for Device Info HW+). It also offers customization options like update interval, showing as a notification, and changing which sensor to use as the CPU temperature sensor from the list of all sensors.

It is important to note that some devices may have blocked access to CPU load and thermal info. In such cases, users can switch to using root to access these features. Overall, DevInfoOverlay is a useful app that lets users monitor their device's performance with ease.