easiest app to restore contacts is Super Backup and Restore. you can backup everything apps, contacts, calendar, messages etc. However if your flashing roms check out this easy way. Before installing new rom in CWM recovery do a backup of current rom. now go through your flash process. then before exiting cwm recovery go into restore, advanced restore and select the backup you just did then select restore data only. then reboot your phone when its done. check that out. every app, every setting you had on your last phone is done. you don't even need to go through the setup process as youre already logged into gmail. makes changing roms a breeze!