I've recently bumped into this answer on SO:
It shows a way to use the Google Maps tile layers using a direct - probably internal - API. It is followed by some comments stating that this is a violation of Google's terms of service. I'll transcribe them here, in case they get deleted:
developers.google.com/maps/terms check out section 10.4e.
Section 10.4e of the ToS states:
No use of Content with a non-Google map. You must not use the Content in a Maps API Implementation that contains a non-Google map.
To me, this sounds more like: I can't use content available in the Google Maps API (such as geolocation, markers/labels for bussinesses and such) in another maps implementation (Such as, for example, OpenStreetMaps).
Am I wrong? If I'm right, is there any other clause preventing use of the tile layers in this way?