I followed this basic tutorial, but I get:
Eroare:redirect_uri_mismatch The redirect URI in the request: urn:ietf:wg:oauth:2.0:oob did not match a register
The URI
urn:ietf:wg:oauth:2.0:oob
is only applicable to those Google client IDs that have been generated for "installed applications".
So to solve your problem you have to create a new Client ID and set Application Type as "Installed application". There you can get ClientId and ClientSecret which you will need.
Create a new Project Here
Select APIs from the left side bar and make sure Drive SDK is ON
Go to Credientials below APIs ,tap on "CREATE NEW CLIENT ID"
Select Installed application and type as iOS and provide Bundle ID (or simply choose "Other")
Copy Client ID & Client secret to use that in your application.
The redirect URI is automatically generated and should prevent the error you are getting.