Hot Apps 4 HOTS (link opens to iTunes) is a free ebook about iOS apps that can be used to help students practice and develop higher order thinking skills. The book takes readers through a series of apps that are aligned to the various parts of Bloom's Revised Taxonomy. Examples and suggestions for app use are included in the book. As Hot Apps 4 HOTS is an ibook, it can only be viewed on an iOS device.
Applications for Education
If your school is one that is rolling-out iPads for student use, check out Hot Apps 4 HOTS to find some good apps and ideas that you can bring into your classroom.
A couple of other good places to find iOS apps for your classroom use are Kinder Town and IEAR.