My hubby likes gadgets, the more buttons and technically difficult it is to use, the better, ........all this stuff is like a foreign language to me...
 
He bought a cell phone holder for his smart phone (Windows 7 phone) He downloaded a 99 cent app called Marathon for bikers, runners, walkers to keep track of miles per hour, distance, elevation, climb/downhill, avg speed, etc etc and it saves the data and compare against previous data.  
 
He loves it !  Of curse, when I tried it, it did not work for me, too many icons to push and remember. He had to push the right button so it would work for me....I have been pushing his buttons for 35 yrs!