Pro Deer Calls is a collection of the most effective Deer calls & sounds on iTunes. Call in Deer with the best calls on the market. Deer Calls lite plays popular calls with the option to upgrade to the pro version and unlock all of the most popular and effective deer calls sounds. Including a new sound of a deer feeder slinging corn. Pro Deer Calls plays over 7 of the most popular and effective deer call sounds. Supports plugging in external amplified loud speakers/headphone to headphone jack for amplifying the volume, so sounds can be heard long distances. Will also route calls through iPhone connector at bottom of unit as well as connect to a bluetooth speaker. ** Note: If you have problems with no sound when playing a call, make sure the mute is not turned on and the volume is up on the device. Test by playing music or sounds that you know work to make sure your getting sound.