On android it is possible for apps to secretly use the camera without notifying the user which creates a security hole.
This app displays a constant notification with such info(either camera is being used or idle) and helps a lot if you suspect the camera on your phone is stealthily in use by someone else.
Source code is available here:
https://github.com/Manuiq/CameraPrivacyControl
![How to Detect a Hidden Camera Using an Android Phone? [ Find Hidden Cameras Using Mobile Phones? ] screenshot 5](https://i.ytimg.com/vi/3e7ZQDJAXlo/mqdefault.jpg)
9Apps 4.9
