Released in June 2008, the iPhone 3G had been widely anticipated for nearly the entire lifespan of its predecessor, the wildly successful iPhone. The iPhone 3G included two prominent features that had been distinctly absent from the original iPhone—3G networking and built-in GPS. These features came at a price, however: the iPhone 3G was slightly thicker than the iPhone, and had reduced battery life when using 3G networking. To mitigate the increased depth, the iPhone 3G featured a curved back, making it thinner on the edges. The iPhone 3G included a non-recessed headphone jack, to the joy of many iPhone customers with 3rd-party headphones.