Design Challenges and Solutions: Review of the 4th International Workshop on Ubiquitous Computing (iUBICOM 2009). - John Halloran 001; Rahat Iqbal; Dzmitry Aliakseyeu; Martinez Fernando; Richard Cooper 001; Adam Grzywaczewski; Ratvinder Grewal 001; Anne E. James; Chris Greenhalgh (BNCOD, 2009)