sms.ac is a service that promises exciting free messaging services on your phone. However, it turns out not to be so free and exciting, especially for anyone in your address book.
Don’t take my word for it. Google on ‘sms.ac’ and read the horror stories. When you sign up, your address book is uploaded to them. Everyone in it will get spammed multiple times (other sites say four times) trying to get you to sign up. If you actually give them your cell phone number, it turns out that most of the messages are premium services that get billed directly to your cell phone bill. Others even report getting charged for messages they didn’t even request. And on top of that, their legal department churns out threatening letters to anyone posting complaints about them, even if the complaints are completely true.
sms.ac is an anagram for ‘scams’.
Stay far away from this one. If any of your ‘friends’ gives them your address, send your ‘friend’ some of these links.