Todd Spangler NY Digital EditorRoku, gearing up for the 2021 holiday shopping season, unveiled the all-new Roku Streaming Stick 4K — priced at $50, the same as its previous-generation model. It’s also releasing the Roku OS 10.5 operating system with a bunch of enhancements, including new voice controls for Netflix and Spotify.The Roku Streaming Stick 4K is up to 30% faster than its previous stick, which enables smoother streaming in 4K, Dolby Vision and HDR10+, according to Roku.