When Apple launched the iPhone X, iPhone 8 and iPhone 8 Plus on Tuesday, one new feature went under the radar: The phones can charge faster than before.

Here's how much more: you'll be able to get up to 50 percent battery in 30 minutes, according to Apple's Tech Specs page for the iPhone X and iPhone 8 and 8 Plus. The catch is, you'll have to pay extra for Apple's USB-C power adapters to do it.

The irony is clear. Apple uses the USB-C charging port on most MacBooks, but the iPhones retain the company's proprietary Lightning port. The fact that you can only get this major battery benefit through a USB-C adaptor signals that Apple's demand to be different actually shuts it out of the fast charging feature. Adapters work, but elegant they are not. (The new iPhones are also Apple's first to get Qi wireless charging.)

Here's the nitty gritty:

Apple says that fast charging is compatible with Apple's 29W, 61W and 87W USB-C power adapters, but to get one you'll have to shell out anywhere from $49 to $79 (or £49 to £79, or AU$69 to AU$109) to get one, and then pay another $25 (£25/AU$35) for the USB-C to Lightning cable.

As another option, the Mophie and Belkin wireless charging pads are said to be getting fast charging (with up to 7.5W of power) through a software update coming later this year. That won't be as fast as other 15W wireless chargers, and is likely still slower than the 29W-to-87W USB-C fast-charge configuration.

Apple did not respond to a request for comment on this story.