It's showing you how fast you'll be going in what gear with the factory setup for the front sprocket and rear sprocket.
The application is designed so that you can have three setups to compare:
Your current setup, stock setup, and what setup you're thinking of trying next.
So you can be like, "Oh, at 6000 RPM in 4th gear, I'll be going 57 miles per hour!"
It's also a good way to compare your bike to your buddy's bike and figure out why his GSXR 750 walks right away from you when you've got your Scrambler pinned in 6th gear