Im not sure if its just the iPhone 4 or for all people but it doesnt work unless you plug it in to headphones or speakers. I put my headphones in and it sounds great and I know it will work but youre not gonna call anything in with headphones. I dont have speakers to use and I think its stupid that to use this app I would have to go out of my way to pay for speakers. I wanted a free app not a $50 app. If they could update it to work with just the phones built in speakers this would be 5 stars but since I have no use for it now Im giving it a 2. I hope the makers of this app read this review and update it cause I would really love to kill some coyotes!
TJ BMX about Predator Calls Pro