http://www.techradar.com/news/amazon-cuts-4k-content-prices-as-apple-tv-4k-goes-on-sale

Earlier this month, Apple announced it would start pricing videos in 4K on iTunes at the same price as HD videos to celebrate the launch of the Apple TV 4K, and there was much rejoicing. 

Apparently, there was a lot of negotiating from competitors, too. Today, Amazon slashed the prices on all of its own 4K videos, making them infinitely more affordable than they were just hours ago.