I've found the mobile app "Bird Field Guide" quite interesting!! Downloaded it just a few days back.. I use it on my HTC Android phone.. but i believe its available for i-phone and i-pad too..
There are free & full version downloads available.
More information is available on the website http://birdfieldguide.wordpress.com/
There are free & full version downloads available.
More information is available on the website http://birdfieldguide.wordpress.com/