The URL syntax where the API token can be used like https://<token>@api.appetize.io/v1/apps is really a browser shorthand for HTTP basic authentication, where the API token is the username, and there is no password. Some browsers support it, but some do not. 
 
If you are receiving 401 unauthorized when trying to use your API token, and you are sure your API token is correct, please try using HTTP basic authentication headers with API token as username with no password.