Attendance2 (iTunes App Store link) is a complete rewrite of the original Attendance app. It is designed to be more general and more customizable. Each course/group is a separate data file so it can be shared with teaching assistants and/or school administrators who also have the Attendance2 app (i.e., a school administrator could collect data files from each of his/her teachers on his/her iOS device). Attendance2 is a universal iOS (iPhone/Touch and iPad) app. The app is optimized for iOS 7 (but still runs on iOS 5.1 and iOS 6.x).
There is a web-based demo here: http://www.dave256apps.com/attendance2-demo/
Since I make about $2 a copy after Apple's 30% cut and taxes, a handful of people have asked how they can pay me for answering support emails. Here is a Pay Pal donate option that you can use if I have answered a support email for you and you would like to thank me.
Attendance2 has many features that the original Attendance app does not have and as of version 2.0 (approved by Apple January 4, 2013), it has all the major features of the original app including importing from Contacts (added in version 2.0). In general the new app is more flexible and more customizable. The second status also allows for participation, or other uses such as using status1 for checkin and status2 for checkout. I wrote the new app from scratch because the original app was written for iOS 2.0 and I could not add many of the feature requests based on the original data structures. Attendance2 was written for iOS 5.0 and higher and allows me to take advantage of many additions Apple made and I re-designed the internal data structures to make it more flexible for new features.
Short Introductory Video
Attendance2 cannot import the attendance records from the original Attendance app since the internal data structures are completely different; however, you can export the names as a CSV file (using the Info Report on the report tab of the original Attendance app) and import that CSV file into the new app. If you were using the original app, it probably makes sense to start using the new Attendance2 app at the beginning of a new term/semester.
If you are using the original Attendance app, you may continue to use it if you want as I will support it at least through iOS 6 (i.e., make certain it works on iOS 6 and fix any bugs). A few of the features (accessing photo library) are broken in iOS 7 due to changes of Apple made, but most of the original app still works. Of course, if you were happy with the original Attendance app, I hope you will purchase the new app.
Creating and scanning QR codes (can also scan bar codes).
Longer introduction video showing more features (made with version 1.x of Attendance2)
CSV Import video
Export roster from Moodle as CSV file and import
Shows how to customize statuses and gives an example for day care centers.
Here is a link to a longer video made by a music teacher who used Word/Excel and their mail merge feature to print out nice folder labels with the QR codes generated by the app. You don't need to go to all this trouble to use QR codes (as the app will even assign unique ID numbers and generate the QR codes for you), but if you want to include other information and print the QR codes, this is a well-done video showing detailed steps to do it.