Autodesk Sketchbook is now Sketchbook Inc, an independent company spinned off from Autodesk in June 2021. Thomas Heermann from Autodesk explained the move and also talked about the history of Sketchbook.
The app is called Sketchbook Pro instead of Autodesk Sketchbook. It's a good move to build a stronger identity for Sketchbook Pro. Over at the Sketchbook blog, they also talked about the transition and what artists can expect.
From what I can see currently, Autodesk Sketchbook that's now on Google Play Store and Apple App Store is still the old version: Autodesk Sketchbook v5.1.7 which was updated more than a year ago. I'm not sure if users will be getting a free upgrade.
For Windows and MacOS users, Sketchbook Pro is US $19.99 each on each platform. Which means if you have to buy two licenses if you want to work on Windows and MacOS. It's still kinda worth the money though considering the features you get and it's a one time purchase. Sketchbook Pro is certainly not Procreate but being about to use it on Windows and MacOS can be very convenient.