You can now start to view your achievements on the Stadia on your mobile phone app. Thank you to EpaddYC for the tip. The loading of the achievements is a little sluggish the at moment so be warned however they do show up. Note playtime and other stats are not included at this time
To access you achievements on you phone you need to :
Click on your friends list icon. This is to to the left of you avatar.
Click on your Stadia name
Click on achievements
Then click onto the game you want to check. This is list may take its time to populate
Then the games achievements should display.
This another positive step for Stadia as they continue to roll out new features. We also have to look forward to the first demo of Crowd Play on Monday.