SAN JOSE - Zipwhip spent the last five years focused on the mobile side of SMS before it realized that the two percent of text messages being sent to landlines and toll-free numbers deserved to be delivered, too.

Leveraging the cloud texting technology along with the mobile, desktop and web apps it already built, Zipwhip’s major challenge for enabling text messaging for existing numbers was navigating the policy issues (i.e. verifying ownership of a number).

Once Zipwhip lights up the number for texting, it sends the phone number into the inter-carrier routing system for text messaging so, essentially, every wireless operator gets a copy of the route that points back to Zipwhip’s cloud, CEO John Lauer said.

Zipwhip has so far been able to sort out the policy issues for SMS and it’s working with CTIA and the carriers to enable MMS on its landline and toll-free services.

“We’re like 50 percent a policy company and 50 percent a technology company,” Lauer said. “When people ask ‘How come this wasn’t done years ago?’ It’s because of policy.”

Zipwhip is up to eight million users now and many of its customers are putting the service to use in unexpected verticals. The Middleton Police Department in Wisconsin has set up its non-emergency number and the National Restaurant Association has allowed members to text in to check on certification test scores.

“To scale to eight million users was a real challenge but we nailed it and we could scale out right now to 100 million users without skipping a beat,” Lauer said.

That opens up Zipwhip’s service to much bigger verticals like health care and public safety. Zipwhip just signed a contract for 130 public safety locations across the entire state of Indiana.

Zipwhip is offering businesses a free trial of the service through the end of the year. After that, there are two monthly packages for Zipwhip: $19.95 for the economy package and $99.95 for the business class package which features group texting, auto-response and other extras.

Between landlines and toll-free, Lauer estimates there are 200 million phone numbers in the U.S. that don’t send or receive SMS, which could lead to a boost for the declining network technology if Zipwhip really catches on.

“If you’re a business with a landline, you’ve got your phone number that’s a really big deal to you. It’s kind of like your dot com domain name,” Lauer said. “You can now add a text carrier, which is really a second carrier to that line just for texting, and that’s us.”