OnRelay is a privately held Unified Communications software company specialising in Cellular Fixed Mobile Convergence (FMC). Founded in 2000 and headquartered in London, the company lists Tier 1 operators and Fortune 500 companies as customers and partners. OnRelay’s Mobile PBX software (MBX) eliminates the need for businesses to purchase and support proprietary telephony hardware. MBX is the first Cellular Fixed Mobile Convergence solution able to completely replace desk phones with mobile phones. OnRelay’s patented Telephony Internetworking Protocol (TINP) works over any mobile network, worldwide. By integrating MBX with the leading open source PBX, sipXecs, OnRelay offers businesses a complete fixed and mobile telephony system. Operators can host MBX as Software as a Service (SaaS), bringing significant cost savings to their customers. Multinational companies can deploy MBX within their legacy infrastructure, capitalising existing investments and bringing mobile under corporate control.