The Week in iPhone Cases: Icy roads
The CardNinja (all iPhone models; $20) is a sleeve that attaches to the the back of your iPhone (or to your existing case, if you have one) and provides a convenient pocket for plastic cards or paper money.
Designed to safely hold cards and banknotes even when it’s upside-down, the CardNinja is available in black, grey, or purple.
http://www.macworld.com/article/2023444/the-week-in-iphone-cases-icy-roads.html
