I'm having some problem with the Tachometer app for iPhone.how check the RPM?

I'm having some problem with the Tachometer app for iPhone. How check the RPM?

There are a lot of details that go into making it work but here is roughly ho it works. It basically takes snapshots of the rotating fan at regular intervals, finds out the center of the circle from those points, determines the angle of rotation per unit time and tells you the RPM on the rotating body.

It works till 200 RPM consistently as of now but we're trying some fancy approaches to make it much faster. I will keep you posted on how that goes.

more information visit the links below

A gauge the measures how fast a motor is running in revolutions per minute. The gauge can represent the information in analog or digital, and is critical when driving performance vehicles.

Apple Tachometer also does the same but I guess that it can't go beyond 150rpm in reality.