If you can not live without your smartphone to run, so do not hesitate, this is the subject for you. My Blackberry snugly there and the window dimensions suggest that most smartphones will feel at ease. However, running means having hot, and this is the downside of this object: it gives even hotter. The material - Neoprene? - Is soft and pleasant, but it's a real heater! However, motorcycle or even by bicycle, provided not to physical prowess, it's perfect. It will give you a rough tan, but when you love (call), it does not count!