ewrapper: operationalizing engagement strategies in mHealth. - Blake Wagner III; Elaine Liu; Steven D. Shaw; Gleb Iakovlev; Linlu Zhou; Christina N. Harrington; Gregory D. Abowd; Carolyn Yoon; Santosh Kumar 001; Susan A. Murphy; Bonnie Spring; Inbal Nahum-Shani (UbiComp/ISWC Adjunct, 2017)