On Thursday, May 11, 2017 at 8:16:44 AM UTC-7, Alex wrote:
Advanced is just a different map view similar to the google-maps option which also requires a login. Both options are available after logging in. There is no subscription fee.

The OLC does invite you to donate - but the only advantage is a smiley beside the claimed flights. To my knowledge the donation is purly voluntary and does not come with any special features.

There is not a fee for Google Maps. There is a fee for Advanced.
Jim