I have played with the Tango Stylus of the iPhone before and the thing works pretty well. The only real issue I had was that the stylus wouldn't fit in the average case meaning it was hard to take with you on the go. Tango has fixed that issue with a new leather case that is designed to hold the stylus and the iPhone.
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The case is called simply enough the Tango Case. It has a custom clip on the side of the case that you can connect the iPhone Pogo Style to for carrying around with you. The case comes in black leather with blue or green trim.
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The leather is full grain with a soft microsuede interior that keeps scratches away from your iPhone. The black Pogo stylus is included with the case and the front of the case flips down for access to the iPhone. You can get the Pogo Case now for $39.95.