Useful and free.
The following is a list of useful free travel apps for smart phones compiled by Vagabond Journey’s business travel correspondent, Rory D
Aloqa- locates you by GPS and tells you whats going on around you (fun stuff), where things are (gas, ATM, food) and more
Google Maps- Free GPS based maps just like on your computer except in real time
WMWiFiRouter- turn your phone into a wireless router for your laptop to hook onto
Evernote- take notes, upload files, take pictures and load to the web
UPC reader* not sure what its called and I think it costs 2.99- scan UPC codes on products and it will tell you what it is and if it can be had cheaper elsewhere
metric converter- convert stuff
Rory D is the business travel correspondent for Vagabond Journey Travel. He is available to answer your business travel questions. Just go to ASK business travel questions and fill out the form. Expect a response from Rory on the site in a couple of days to a week.