1)   Prime Number Calculator 4.6.1
Calculate the prime numbers between two limits. It uses a deterministic test and uses the Sieve of Eratophenes logic. Recommended on The Math Forum @ Drexel (University) for Middle School, High School and College, ages 6+. 99¢ only.

 2)   Factor Calculator 5.6.2
Calculate the factors of any number with a single click. Small application window allows simultaneous use with Word, Outlook, Excel, etc.. Recommended on The Math Forum @ Drexel (University) for Middle School, High School and College, ages 6+. 99¢

 3)   Geodesic Red 3D Screensaver 1.0
Three 3D screensavers for the price of one. Giant 3D Geodesic Ball floats, bounces, spins on your desktop. 3 colors - red, blue, yellow. Download Red to try. When you buy Red get links to Yellow and Blue. Change colors with your mood.

 4)   Primality Tester 5.3.2
Test any number for primality with a single click. It uses a deterministic test and uses the Sieve of Eratophenes logic. Recommended on The Math Forum @ Drexel (University) for Middle School, High School and College, ages 6+. 99¢ only.

 5)   Prime Integer Observatory 1.0
This application illustrates the notion of an integer’s factors, and of the related property of integers called primeness, or primality. An integer is called prime if it is the product of only one distinct pair of integers.