The Amazon Appstore Android app was just updated to version 2.3, which finally raised the maximum application size that can be downloaded over a mobile connection from 20MB to 50MB - something we've been asking the company nonstop for over a year. I understand why they set the default to 20MB, but enforcing a max, especially on 4G (Sprint has unlimited 4G, for example) didn't make sense. After all, it's my data, I should be the one to decide how to use it. Can you say "finally" a few more times? I can.
The 50MB limit still leaves that unlimited option to be desired, but it's a huge improvement. In comparison, the Play Store app limit continues to be 50MB - the recent 4GB bump affects only additional downloads. However, since you can still download a few hundred megabytes of data on a mobile network without issues from the Play Store, you are never actually forced to use Wi-Fi. With The Amazon Appstore, not so much.
Furthermore, today's update should fix the issue where notifications about app updates would still show up even though they were completely disabled in the settings, which was the largest gripe after the 2.2 update in early March.
The rest of the changes are minor - stability enhancements and minor bug fixes.
Grab the update by going to the Appstore app > Settings > Version and Release Notes > Check for Updates or just wait for a notification (it should show up even if you disabled notifications before).