Periscope Camera is a free Android app developed by RACOO. As its name suggests, it works like a digital periscope that helps users find hidden objects in dark and narrow places. This app is especially useful for checking the back of a computer where a problem occurred or finding lost objects like car keys that have fallen behind the desk.

The interface of Periscope Camera is simple and intuitive. Users just need to hold their phone camera up to the area they want to view and the app will display a live feed from the camera. They can then adjust the angle and zoom in or out to get a better view of the area. The app also includes a flashlight feature, which can come in handy when searching in dark places.

Overall, Periscope Camera is a useful tool for anyone who needs to find hidden objects in dark and narrow places. It is easy to use and the live feed feature provides a clear and real-time view of the area. Plus, it's free to download from the Google Play Store.