Direct Combination is a principle, a computational framework, and a methodology, for simplifying device inter-operation and interaction between digital and tangible objects. Direct Combination was cited as a new user interaction technique with the potential to simplify a wide range of user interactions with pervasive technology by industrial research labs including Sony Tokyo (Rekimoto, 2004, Rekimoto et al., 2003, Kohno et al. 2004), IBM Global Services (Bardram et al., 2003), BT Exact (Warren, 2004), Telecom Italia (2006), Xerox PARC (Edwards et al, 2004), Healthcare professionals (Bardram et al., 2003), and theorists such as Beaudouin-Lafon (2000) and Kjeldskov (2003).
- Sony Japan. The Head of Research at the Sony Interaction Lab, Tokyo, noted in a series of papers that the ease of interacting with three Sony prototypes - FEEL phone (Kohno, Ayatsuka and Rekimoto 2003) SyncTap (Rekimoto, Ayatsuka and Kohno 2003), (Rekimoo, 2004) and TACT (Kohno et al, 2004) - could be improved by applying Direct Combination techniques.
- Telecom Italia. A consortium including Telecom Italia (Bartolomeo et al, 2006) began development of a highly portable "Simplicity Device" giving access to a wide range of mobile services employing use of Direct Combination.
- IBM Global and the Centre for Pervasive Healthcare in Aarhus (Bardram et al., 2003) cited Direct Combination as providing a way in which design for roaming medical applications might be improved.
- BT Exact (Warren, 2004) noted Direct Combination as a way of achieving simplicity in ubiquitous interaction.
- Application areas cited include: device inter-operation, healthcare, network control, location based services, games, music, serendipitous integration, simplifying Mobile services.