Honestly, for most cyclists, knowing the actual gear inch ratio of every one of your gear combinations is a good recipe for overkill. To the true cycling geek however, you can never have too much information. If you’re one of the latter, take a look at this iGear calculator app for all Apple devices.
iGear is a free app that allows you to input your exact drive train specifications to figure out your exact gear ratios. Whether you’re wanting to build a custom cassette for your road bike, or wanting to see how different chainrings will affect your XX1 drivetrain the app has you covered. There is also an iGear Pro app available for $0.99 that includes the ability to compare two different drive trains on the same screen for the iPad app and more built in cassettes.
Check out the rest of the screen shots after the break.
