As it showed off a 20,000-square-foot expansion to the Waltham campus where its 4G LTE technology was developed, Verizon demonstrated novel applications for the wireless networking technology. “Any of our (business) customers can have the opportunity to visit the innovation center, and partner with us to create something that might be good for them as a company,” said Christine Berberich, president of Verizon’s New England business. Verizon is working with big firms such as Swedish mobile technology company Ericsson on products like the “office in a box,” a portable box providing wireless 4G LTE phone and Web service. On the smaller side, Verizon showed off a 4G-enabled telepresence robot made by Nashua, N.H.’s VGo Communications. VGo has been working with Verizon for about 2 months on developing a 4G-enabled version of its robot, according to VGo vice president of marketing Ned Semonite. Verizon offers the companies lab space and engineering time at no charge. This helps create more 4G LTE enabled gadgets, creating more potential service subscribers for Verizon, Semonite said, and it saves companies like VGo time and a few hundred thousand dollars. The 15-employee VGo hopes to go to market with the 4G robot by the end of the year. “Without their help, we maybe wouldn’t have chosen to do this at this stage,” Semonite said.