The Blackburn VIP Zip Wallet features a generous 5.5" x 3.5" x 1.5" size that is still small enough to fit in a jersey pocket. It has several storage options including a water resistant ID and currency sleeve and phone/MP3 player pocket with a clear cover. A special, water resistant zipper helps to keep the contents dry.
I chose the Zip wallet as an alternative to the Beaker Concepts wallet because of the poor reviews(potential scratching from zipper) of the Beaker model. While the Iphone is certainty protected in the Zip wallet, the Zip wallet is just too big to feel comfortable in a jersey pocket. The size of the "wallet" feels more like a small saddle bag. Also, like many people I know, I have my Iphone enclosed in case. I found it difficult to fit the encased Iphone in the wallet sleeve designed to hold it.