The applications for iphone are staggering and I am currently seeding my first iphone application - Dogbook. While at first you wouldn't believe there could be an iphone app for your dog, it is actually incredibly useful. You can locate the nearest park anywhere in the world via your location on GPS, you can see what other dogs are nearby should you lose your dog you can send an 'arf' alert to other users within 15km with a photo of the dog so it can be found again. Iphone makes life that little bit easier once more. Download it for free from itunes
