ID reader USA reads the machine readable zone from the back page of US Passports. Thats the two lines of 44
characters containing a persons name and the number of the passport. The app reads the MRZ right on the iPhone or iPad!
The app can store IDs as you read them and it can compare ID against its list of IDs.
You can edit the ID list with iTunes FileSharing.
You can also send a decoded ID to a URL of your choice (you can set this in settings).
The app has SCAN mode where images are taken continuously until a valid 2 line passport MRZ is found. The currently decoded ID string is displayed to help out senior users.