3. If you have a smartphone and an appropriate mobile network access plan, download apps for Pandora.com and Grooveshark.com. Use these two services for a few days to listen to music. Prepare a presentation that compares the services, listing the strengths and weaknesses of each. (Caution:These services use a lot of bandwidth, so you should check with your cell phone carrier prior to using these handhelds to make sure you won’t incur unexpected expenses on your phone bill.)