Adam if you are looking at commercial libraries for Barcode recognition on Android you can try LEADTOOLS Barcode SDK.The LEADTOOLS SDK has support for a variety or Barcode Symbologies including Aztec.
There is a demo application on the Play store that you can test as well. LEADTOOLS Barcode scanner application
This demo is developed with the LEADTOOLS Barcode SDK for Android. Here are some screenshots:
The actual Barcode recognition is done with minimal code:
BarcodeData data = null;
data = mBarcodeEngine.getReader().readBarcode(<image to be processed>, <screen coordinates to search in>, <barcode symbologies to search for>);
Source code for the barcode demo above is included in the 60 day trial version of the SDK that you can download from the LEADTOOLS Site.Please note I work for the company that develops this library.