Frankly that device has been kicked around for a long time. No secret today.
Have you ever heard that iPhone and Android smart phone can be turned into GSM mobile phone? The secret is using a mini GSM dual sim standard phone. Connect with iPhone and Android smart phone through bluetooth, which is only credit card size.
<img class="decoded" alt="http://g-ecx.images-amazon.com/images/G/01/aplusautomation/vendorimages/fd357b3d-601d-43a2-bf6f-7e1cc7dabc88._V331068301_.jpg" src="http://g-ecx.images-amazon.com/images/G/01/aplusautomation/vendorimages/fd357b3d-601d-43a2-bf6f-7e1cc7dabc88._V331068301_.jpg" height="271" width="469" />

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