工具箱：手电筒＆指南针＆心率检测 app for iPhone and iPad

1、 heart rate monitoring, anytime, anywhere to view the current heart rate, good for good health.
2、decibel instrument, real-time sound measurement, let your cell avatar decibel device, easy to monitor the surrounding environment volume, away from the noise environment.
3、compass, level together for a convenient use, no longer worry about not find the North.
4、flashlight, three brightness adjustment, SOS emergency mode, features readily available.
5、protractor, take pictures to measure the angle, no dead ends use the scene.
6、random number, real random number generation tool
7、ruler, cursor free to slide accurate measurement
8、commonly used gadgets, math tools, cameras