Darren Murph of Engadget writes:"This ain't the first rodeo for Visa and DeviceFidelity, and if we had to guess, we suspect it won't be the last. Just a few short months after teaming up to bring contactless payments to any mobile with a microSD slot, the two are at it again -- this time aiming for the oh-so-tantalizing iPhone market. Reportedly, the tandem is toiling away in an effort to concoct a protective iPhone shell with a secure memory card that hosts Vista's contactless payment app, payWave. As it stands, the product would only function on the iPhone 3G and iPhone 3GS, leaving upcoming iPhone 4G / HD / Barhopper buyers out in the cold. As with any other payWave-enabled handset, this would allow users to simply tap and go when checking out, a process that our pals over in Japan have had down for centuries now. If all goes well, market trials of the payment-enabled iPhone are set to begin this summer, or approximately six months too late for anyone to seriously care."