On a number of AT&T phones (including but not limited to the Samsung Captivate, HTC Aris), AT&T has decided to prevent users from purchasing applications outside the Android Market. To find out if your phone supports purchasing non-market applications, do the following:

  1. From the home-screen of your phone, press the menu-button
  2. Tap “Settings”
  3. Tap “Applications”
  4. In this menu, most phones outside AT&T will have a checkbox called “Unknown sources”, that users can check to allow the purchase of applications outside the Android Market. If your phone does not have this check-box, you will not be able to use Amazon Android Apps.
    1. We are currently unable to support devices that are not allowed to purchase apps outside the Android Market.