The HTC Desire 620 and Desire 820 have began selling in parts of Europe, namely the UK and Germany. The Desire 820 will be available to order from mid-January, while the Desire 620 will arrive in store shelves a week later. In the UK, the phones have freshly landed on retailers Mobiles UK, with CarphoneWarehouse, Clove and others soon to stock them. The Desire 620 will be available for free on £15/month contracts, while the Desire 820 will be a gift on £18/month deals. Naturally, they'll be available SIM free too, but actual pricing isn't yet available. However, in Germany both phones are already available SIM-free for 319 and 271 for the Desire 820 and Desire 620, respectively. This gives us a rough idea for the UK pricing, which currently translates to £249 for the Desire 820 and £211 for the Desire 816. The Desire 820 has a 5.5-inch, 1280x720px display, 13MP rear and 8MP front cameras as well as BoomSound speakers. It sports a Qualcomm Snapdragon 615 (MSM8939) chipset, which has an octa-core CPU with eight Cortex-A53 cores. The Desire 816 on the other hand features a 5" 720p display, 1GB of RAM, and 8GB of expandable memory and a 64-bit Qualcomm Snapdragon 410 chipset. Source Source (2) Source...
Source: http://www.gsmarena.com/htc_desire_820_and_desire_620_launch_in_the_uk_and_germany-news-10725.php