Step Challenge is a mathematical challenge.
Starting with a given in the first line, just carry out the operations specified on each line to derive a final answer. Each operation acts on the result of the line above. As you progress, you can, if you like, click on the result box of any line to confirm all the results down to that point.
There are three levels of difficulty, each with a suggested time in which to complete the challenge, from a 30-second challenge upwards.
Full Help facility.
Also available from i.compactfun.com if you cannot download from the Android Market. Versions for iPhone, iPod Touch, iPad, Nokia, Windows PCs and Macs also available from there.