Truphone

Cellnetrix GmbH is a research and development company headquartered in Hamburg, Germany, with an additional office in Russia. Founded in 2006, the company specializes in the development of embedded software aimed at enhancing the reliability and security of wireless mobility and Internet services. Cellnetrix focuses on operating system development for smart cards and secure network-connected devices, particularly universal subscriber identity modules (USIM) used across various mobile networks such as GSM, UMTS, and CDMA. The company's offerings include secure mobile applications and comprehensive Over-the-Air post-issuance management services for (U)SIM and R-UIM cards, utilizing a proprietary OTA platform. Cellnetrix's solutions adhere to industry standards set by organizations such as the Open Mobile Alliance and 3GPP, and are built using widely adopted programming languages. Its clientele includes notable telecommunications companies, enabling them to integrate advanced security features and deliver innovative products. As of December 31, 2017, Cellnetrix operates as a subsidiary of Truphone Limited.

CoSwitched is an Internet of Things Mobile Virtual Network Operator focused on democratizing internet access for devices while facilitating advanced voice communications between machines. The company aims to enhance connectivity for a wide range of devices, enabling them to operate more effectively and interact with each other through rich voice communication capabilities. By prioritizing accessibility and innovation, CoSwitched is positioned to play a significant role in the evolution of machine-to-machine communication and the broader Internet of Things ecosystem.

SIM4Travel is a London-based company that specializes in providing mobile communication solutions for travelers. It offers a temporary travel SIM that enables users to make international calls while benefiting from free incoming calls. Originally known as SIM4Travel Holdings plc, the company changed its name to S4T Plc in 2008. While it currently does not have significant operations, it has previously focused on delivering low-cost mobile phone solutions to enhance the travel experience. SIM4Travel operates as a subsidiary of Software Cellular Network Limited and is exploring new technologies and market opportunities.