In IOIO and Google ADK boards you need to have deep Android development experience to use them (have to build your own Android app or use an open source one) and they are not plug-and-play devices, but we are. With our product, you can download the app directly from the Google Play store, hook 1Sheeld to your Arduino and you are good to go.
Mainly due to cost, we wanted to make our product as affordable as possible! The HC-06 is one of the cheapest reliable adapters on the market. However, we are actively considering a change to a more powerful longer range adapter.
We were hoping to do it, but due to some technical limitations and constraints on iOS, we are afraid we won’t be able to develop a solid solution anytime soon. The Android platform is more open when compared to iOS and it more effectively supports the core functionalities we are offering. Our key constraint on iOS is the inability to run the app in an always on background mode,
Our current testing has been preformed on Android 4.0 (Ice Cream Sandwich) and above but our app doesn't require any high-end smart phone features(At least for most of the available shields on the app). In the final version, we intend to support Android 2.3 (Gingerbread) and above - provided that the mobile device supports Bluetooth and has the basic peripherals and sensors (e.g., You can't use a Gyroscope shield on a device that doesn't have the Gyroscope hardware).
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