SMS is the ugly stepchild of mobile applications, but if you’re looking for a simple way to reach a huge swath of people, SMS is the way to go.
After all, smartphone penetration is still relatively low within the U.S. and global markets. And for some tasks, you might not need something as complicated as a native or mobile web application.
Perhaps you want to launch an autoresponder or send interactive outbound messages. Maybe you want to run an SMS-based marketing promotion or build a self-service app for customers. You could even set up a voting app à la American Idol.
SMS is a great way to reach a much larger consumer base with these kinds of simple messages. And due to the simple fact of technological evolution, building an SMS app has never been easier.
SMSified is a new and relatively easy way to build SMS apps with a REST API. The service provides an SMS gateway that works with the Big Four carriers (AT&T, Verizon, Sprint and T-Mobile) as well as Virgin Mobile and MetroPCS. Currently, SMSified apps work within the U.S. only.
Source: http://mashable.com/2011/05/19/smsified/