No lag time or glitches like some Androids. The coiled one is great for when youre listening to music on the go and dont want to worry about accidentally rolling over the cord with your chair or tripping over it. I also found that using this in a standing position was very challenging unless you have something nearby to grab for balance. Of course the first song that she wanted to sing was Let it go ??! My personal opinion is it is not worth wasting your money on. It?s so difficult to find a sturdy hard sole slipper for kids, so I was really excited to come across these. Pros - looks great, easy to use, app is simple, HR monitorCons - terrible sound, ear buds fail to connect or only one or the other connects, Bluetooth connection spotty, blood pressure way off, pedometer way off. I also really like the look of them. Che delusione! Del audio no puedo hablar por el momento .