Egan and Hengst publish the games made for this project under Classroom Focused Software. 'Line 'em Up' is currently on version 1.4.4. It is available for free from Apple's App Store. More information about Classroom Focused Software can be found here.
The overall aim of the game is quite simple. The player is given a series of number tiles and must put them in sequential order from smallest to largest.
The program features three options for altering gameplay. First, the player can choose the number of total tiles that must be assembled. The options here are 10, 15, or 20. Secondly, the starting number of the sequence can also be adjusted. Here your choices are a preselected number from 1-13 or to have the computer randomly pick the starting number each time a new line is created. Lastly, the player can chose to have number tiles appear one at a time (one pile), all at once (spread out), or have the computer randomly alternate between the two (surprise me).
In the end, the program is very simple and frills free and that's what I like about it. It doesn't have a bunch of sugar coating on it to try to artificially simulate 'fun.' Think of it less as a video game and more like a paperless solution to the classic tile activities many if us probably remember from our youth.
The major benefit to me of having this as an app is students can no long lose their tile cards. My experiences with small paper cutouts and small students has not always been a pleasant one. Some students lose cards and some magically gain duplicates. The end result is the teacher wasting time resorting baggies at the end if the day. Well hallelujah! This app removes the tedious task of making sure your math activities have all the correct parts and for the wonderful low price of free on top of that!
Line 'em Up can be found here or by searching the App Store.