We are coming up with an accessory module that is an external battery, 9-axis sensors and a bluetooth module to allow Archisketch to be standalone. That means, Archisketch doesn't have to be attached to your phone any longer and still communicates with your phone regardless of your model.
Please check our updates to stay in tunes with this module in development :-)
We were considering Wifi as well but compatibility became an issue for Apple devices when we choose Wifi. Unlike Android that promotes open platform, Apple platform is restricted in a way that only apple devices are openly sharable using Wifi. Since our device is serving both Apple and Android users, we had to choose Bluetooth at this time.
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