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Cellnetrix is an R&D company focused on the development of software which makes wireless mobility and Internet services more reliable and secure. The company implements software on different embedded platforms, first of all, for universal subscriber identity modules (USIM) for various mobile networks such as GSM, UMTS or CDMA, as well as WLAN and Internet, provides secure value-added mobile applications and full-scale Over-the-Air post-issuance management services for (U)SIM and R-UIM card based on proprietary OTA platform. Embedded software solutions delivered by the company are based on the de facto industry standards maintained by Open Mobile Alliance, 3GPP, ETSI and Global Platform and use widely adopted Sun's Java programming language.

CoSwitched is democratizing devices’ access to the Internet and at the same time enabling rich voice machine communications. CoSwitched is an Internet of Things Mobile Virtual Network Operator. CoSwitched - Machines also have a voice!

S4T Plc does not have significant operations. It intends to explore for new technologies and market opportunities. Previously, the company was engaged in the provision of access to a low cost mobile phone solution to travelers. It was formerly known as SIM4Travel Holdings plc and changed its name to S4T Plc in November 2008. The company is based in London, the United Kingdom. S4T Plc is a subsidiary of Software Cellular Network Limited.