The application is not compatible with the best androids smart phones released in the market oftenly, then you have to wait long time to Dexcom to get it work with a smart phone and then you can use it, after 6 or 8 month later you create a case with Dexcom.ex. they have compatibility with the Older smart phones, so, who will have these models availables? now almos all of these models are not availables in the market or they are obsolete. User's recommendation: not to but this device.