/// Exclusive: Facebook Cuts Off Access to Voxer Over Competition Concerns
Facebook is facing allegations from a small rival that the service is acting decidedly antisocial. Mobile communications service Voxer tells AllThingsD that Facebook has cut off access to the company’s social graph over competitive concerns. Voxer CEO Tom Katis told AllThingsD that the company got an email on Thursday saying that Facebook wanted to hold a phone call to discuss possible violations of a section of the company’s terms of service. The section in question centers around the use of Facebook’s social graph by competing social networks. Facebook has been increasingly focused on evolving its messaging service onto phones , and this week expanded its iPhone app to include free voice calling to other Facebook users . Voxer offers a mobile app that lets its users communicate with one another via voice, text and other means, including a walkie-talkie-like service. Katis said past discussions with Facebook have always been cordial and that the concerns appeared to come out of the blue. “Yesterday’s call was the first time I ever had any inkling that something like this would happen,” Katis said. It’s unclear if Facebook has similar issues with other mobile voice and texting services. Whatsapp and Kik, two other services, say they don’t use Facebook’s programming interfaces in conjunction with their products. A Facebook representative was not immediately available for comment. The move won’t have a major impact, Katis said, noting that Voxer uses Facebook mainly to allow those new to the service to connect with their Facebook friends already using Voxer. Only about a third of those signing up for Voxer use their Facebook information and he said long-term engagement is the same for both those that do and don’t use Facebook at sign-up. Voxer, which this week launched an expanded Android app, raised $30 million in venture funding last year and has tens of millions of users, according to the company.