Our API directory now includes 255 SMS APIs. The newest is the Msg2send API. The most popular, in terms of mashups, is the Twilio SMS API. We list 171 Twilio SMS mashups. Below you'll find some more stats from the directory, including the entire list of SMS APIs.
Clickatell, a leading mobile messaging and global communications solutions provider, has just announced the launch of the new Connect API allowing developers to integrate into their web and mobile applications in-app Short Message Service (SMS) functionality.