This is part of a really good review of Movies Anywhere on the site High-Def Digest: UPDATE 10/17/17 DIRECTLY FROM APPLE: Apple is ONLY upgrading **iTunes Store purchases** to 4K. Everything else will stay at the original purchase or redemption resolution, be it 4K or HD. To clarify... If you PURCHASED a movie or REDEEMED a Digital Copy IN iTunes AND it's available in iTunes in 4K, you get a free 4K upgrade and will be able to play that back in 4K on the Apple TV 4K. If you PURCHASED a digital movie in 4K somewhere else, like VUDU, AND it's available in iTunes in 4K, you'll be able to play this title back in 4K on the Apple TV 4K. If you REDEEMED a Digital Copy code from a 4K Ultra HD Blu-ray somewhere else AND it's available in iTunes in 4K AND that specific movie studio allows for 4K redemption on this specific title, you'll be able to play that back in 4K on the Apple TV 4K. But... If you PURCHASED an HD version of a movie on VUDU, or one of the other streaming services, it will only playback in HD even when there is a 4K copy available in iTunes. If you REDEEMED a Digital Copy from an HD Blu-ray in Movies Anywhere or VUDU or Ultraviolet, it will playback in HD even when there is a 4K copy available in iTunes. Please also note that some studios sell 4K Blu-rays with "HD" Digital Copies included. With that said, it's still not always easy to actually check the resolution of redeemed titles -- especially since 4K HDR copies are only supported through certain equipment. For example, looking at my iTunes library on a Windows PC shows everything as being in HD. Likewise, since the Apple TV 4K upscales everything to HDR, it's not always a reliable way to determine what native version you own either. Instead, users might need to check the iTunes Store or TV app on their iOS 11 devices to see if the titles are listed as native 4K HDR or Dolby Vision. To check the playback resolution of a movie on your Apple TV 4K, swipe down on your remote during playback; this reveals an INFO tab along with the playback resolution. Keep in mind that you can't check on your display because the Apple TV 4K is set up to output at one constant resolution based on your display's capabilities. Finally, though I didn't experience any major delays when redeeming titles, some of my colleagues and our readers have experienced some hiccups in that regard. Our editor, Michael S. Palmer, noted a 32-36 hour delay before his redeemed copy of War for the Planet of the Apes was added to iTunes. Later redemptions for Bridge on the River Kwai & Close Encounters through MoviesAnywhere.com were instant across all the apps, though, so it looks like the delays are being fixed.