Check out Pure360 – from their website it seems like they have both SMS services and integration with Salesforce. I can’t vouch for their service as I’ve never used it, although I did used to live about two minutes from their offices in Brighton! The other option would be something like Infusionsoft. I’m pretty certain that they have SMS functionality, and would be very surprised if they didn’t integrate with Salesforce.
While email is the most mature (that sounds better than “old,” right?) form of digital marketing, there’s no shortage of marketing technology innovation in this area. Both startups and established vendors continue to develop new capabilities for formatting, targeting, sending, and monitoring the impact of email messages, as well as functions like list building, inbox management, video email, deliverability, branding, custom email signatures and more.