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.
AvidMobile, mobile marketing solutions provider, gives developers two-way access to its mobile marketing platform through the AvidMobile API. The two-way approach to an API strategy allows AvidMobile users to better engage targets and track success. The API is available to build a custom app upon, or users can simply send and receive SMS messages from existing apps.