Kitokito: supporting impromptu collaboration in participatory sensing using smart camera phones. - Hiroki Ishizuka; Shun Fukumoto; Tatsuhiro Nishimoto; Ryo Fukuhara; Tatsuya Morita; Keiji Sugo; Niwat Thepvilojanapong; Shin'ichi Konomi; Kaoru Sezaki; Ryosuke Shibasaki; Yoshito Tobe (SenSys, 2010)