I found out about gsmsync on a very old thread at

http://www.kryogenix.org/days/2005/02/16/synchronisation

where someone calling themselves Anton Antropov said

Thanks for your attentions for http://www.gsmsync.net

We will always stay free of charge, because it's not a commercial service for our company.

The service may well be worth the money now being charged but I would not like to pursue a service advertised as free when it isn't.

Please let me know how to unsubscribe and remove my membership details. Thank you.

You could delete account from "Profile" section

But what if i can't access my profile because of negative balance ?

At the time when I registered
This service was free of charge There was
no demo.

Now I need to back up my data.Kindly give suggestions.