Magnetic Counter - RPM Meter, developed by SailRacer.net, is a free Android application that counts and measures the number of rotations per minute (RPM) of any rotating object. The app is easy to use and requires the user to attach a magnet to a rotating disk and place the phone close by. Every time the magnet passes the phone, the app counts it and displays the RPM.

This application is ideal for DIY wind turbine projects when making coils or when there is a need to count RPMs. The app allows the user to change the magnetic field margin by pressing and holding the screen. Magnetic Counter - RPM Meter is a useful tool for anyone who needs to count and measure the rotations of any rotating object.