released a mobile study aid - Math to Go; it is for PDA's running Palm OS version 3.0 and higher. a bit pricey, but I would have loved to have something like this back in my prep days. You would never forget your math book anymore and would always have it with you. aya-yay.
<a href="http://www.kaptest.com/repository/templates/Lev5InitDroplet.jhtml?_lev5Parent=/www/KapTest/docs/repository/content/Business/GMAT/Courses_and_Services/Mobile_Options&ProductId="> Math to GO </a>
Founder of GMAT Club
Just starting out with GMAT? Start here... | Want to know your GMAT Score? Try GMAT Score Estimator
Need GMAT Book Recommendations? Best GMAT Books
Co-author of the GMAT Club tests
Have a blog? Feature it on GMAT Club!
GMAT Club Premium Membership - big benefits and savings