Mark Coppin does an excellent job of e-mailing out free apps. Typically these apps are free for a day or two, so you need to download them right away. They are usually aimed at special needs students, but like most assistive technology, they benefit everyone. When you download them for free, you can put them on as many devices as you’d like, forever.
E-mail Mark Coppin and have him add you to his e-mail distribution list for free apps.
Mark is a 2009 Apple Distinguished Educator.