I don't wanna copy another persons findings but I got this from a user at resetera ,I dont know how to copy twitter so i'll copy and paste reseter said
- The achievements system won't have a UI at launch, but it will still capture achievement so you can see them when a UI is available.
- Only the Founder's Edition Chromecast Ultra will support Stadia on launch day. Existing Chromecasts won't
- Family Sharing is not available at launch. Recommended to just buy a second version of a $60 game on your account for a kid or other family member to play with, and then eventually be able to share it
- Stadia on iOS will arrive eventually
- Apparently, you need your phone to buy games for Stadia, implying that there's no web UI currently
- Stadia Buddy Pass will not be available to Founders at launch
from me: Microsoft didn't abandon xbox when it lost billions on both xbox 2001 and xbox 360, but since this is google if they see this failing might cancel stadia since they have a history of cancelling anything quick , other than that this is a big yikes .
I game on all consoles and PC