Stage Ib Trial of mSMART With Varenicline

The primary aim of this study is to conduct a 60-patient feasibility, acceptability, and preliminary efficacy study of mSMART (Mobile App based Personalized Solutions and Tools for Medication Adherence of Rx Pill), a smartphone application ("app") for improving medication adherence among substance users. The investigators will compare 2 groups of cigarette smokers undergoing a quit attempt with varenicline (Chantix): a) an experimental group using the mSMART app on their smartphone and a MEMS Cap (Medication Event Monitoring System, a smart pillbox that will a record a date and time-stamped medication event whenever pill box is opened and closed, and thus allow for primary measurement of medication adherence) and b) a control group using the MEMS Cap and mobile web-based surveys on their smartphone.