Twilio is adding a twist to its MMS service, which lets developers embed picture, video and other multimedia messaging into their apps. It’s now adding MMS support for regular 10-digit phone numbers, wherever that number happens to terminate. That means companies can now use a single phone number for all of their customer communications, whether its voice calls, text messaging or multimedia messaging. The capability isn’t entirely new. Companies like Zipwhip and Bandwidth already offer SMS-and MMS-to-landline services to their business and telecom customers and carrier like Frontier Communications have already starting offering offering it to local businesses. But this could be a very powerful tool for Twilio’s core developer customers because it lets them set up visual two-way communications with their customers, said Jeff Lawson, CEO and founder of Twilio.