I am a 54 year old eccentic Grandma. I've always had a secret desire to ride a unicycle & learn to juggle. Thanks to eWheels, I am halfway there. The eWheels team is fast with responses and even called me to explain the smart phone applications. I was leery about having an app but they explained how the app is only required to unlock the wheel after shipping. In my third week of Unicycle practice riding my axil jammed. They did the troubleshooting & solved my problem at no extra charge. I am pleased with eWheel & the friendly, helpful, prompt, service. I love my KS14D. It is just the right size for me. I have taken two significant tumbles in my one month of ownership. Grandma says, "Gear Up!" Because you never know which direction you might go when you inevitably lose your balance. But it is so fun! It's like floating on a cloud. EWheel reps can get you going. What are you waiting for? See you at the park.