The iGagitz armband that I have is labelled as a jogging armband / sports armband, and it should work fine in most sporting situations. Getting the iphone into it is quite an effort, and you find yourself pressing the various buttons on the phone as you do so. You also have to remove any protective bumper that you might already be using for your phone. Once the phone is snuggled up inside the armband, all the controls are fully accessible and the swiping is surprisingly unaffected by the plastic front screen cover.
The armband is supposed to be rainproof (water resistant) although I haven't tried using it in wet conditions yet. The armband is a bit on the sweaty side, but the convenience of having it accessible yet hands-free is a big bonus.