Macworld When the iPhone 15 and iPhone 15 Pro arrive this fall, they will bring a slew of upgrades, including better cameras, refined designs, and a switch to USB-C. But if the latest rumors are true, the biggest reason to upgrade from an iPhone 12, 13, or even a newer iPhone 14 will be battery life. According to a Weibo report from an alleged Foxconn source (via IT News), every model of the iPhone 15 will have a bigger battery when they launch in September. That’s not a huge surprise, as Apple often increases the size of the battery year over year, but this year’s bump is much bigger than usual: iPhone 15: 3,877mAh iPhone 15 Plus: 4,912mAh iPhone 15 Pro: 3,650mAh iPhone…