Plug Sound is a system notification app that can play a sound when you connect or disconnect your device from a charger. This is intended to help you better understand the beginning and end of charging when using an unreliable charger. It plays similarly to the built-in notification sounds.

This is a tiny and simple app that doesn't have any complicated options or settings. It has one button that notifies you after you plug or unplug your device. With this app,  you will never overcharge your phone.