I mean services which can be used as platform, or as part of product for building diffrent kinds of new web/mobile appications/services.

Examples of things like that:

http://quickblox.com/

http://aboutecho.com/

http://www.kinvey.com/developer/features

http://corp.vivox.com/gaming-solutions/download-c3.html

http://www.exitgames.com/

http://apsalar.com/

https://vostopia.com/developer/

http://www.twilio.com/

http://www.stackmob.com/

http://www.demonware.net/

If you don't know answer, please fell free to write about interesting backend services that you know.