Pocket Bubble Level is a free Android app that transforms your smartphone into a bubble level (spirit level). With four different viewing options, this level can calibrate with all four sides as well as show the angle and slope in percentage or roof pitch. It also comes with several sound effects and orientation locking.

The app is compatible with popular Android devices like Samsung Galaxy, HTC, Motorola, Xiaomi, Huawei, and Sony. Pocket Bubble Level is a handy tool for DIY enthusiasts, carpenters, architects, and anyone who needs a quick and reliable way to check if a surface is level.

Overall, Pocket Bubble Level is easy to use and provides accurate readings. It is a useful addition to any smartphone and is highly recommended for those who need a spirit level on-the-go.