Crush the Crave (CTC) intervention group will receive a quit smoking smartphone intervention via the internet that is based on scientific findings related to tobacco use among young adults. It is a multi-component intervention informed by evidence on quitting smoking. The app was developed with the input of key experts in the field of smoking cessation, was assessed against Fiore's practice guidelines for treating tobacco use and dependence, and was tested with eight focus groups of male and female young adult smokers (n=57) on functionality, look and feel and usability, as well as being piloted by over 300 smokers.

The control group will receive an evidence-based self-help guide known as "On the Road to Quitting"(45) that has been developed by Health Canada for young adult smokers. Participants will be able to both view the self-help guide via the internet and will receive a printed version of the guide.

Crush the Crave (CTC) allows users to customize a quit plan by choosing a quit date and then deciding whether to quit now or cut down the number of cigarettes they smoke every week up to the quit date. CTC reminds users of money saved and health improvements. Based on contingency reinforcement, rewards are provided, which smokers can then choose to share with their social network via Facebook. Supportive text messages tailored to their specific quit plan and where they are in the quitting experience are provided. CTC allows tracking of daily smoking habits and cravings as well as craving triggers or psychosocial determinants by recording when, where and why smoking occurred. Online distractions to help smokers deal with cravings are provided.

30 day point prevalence of abstinence at 6 months,operationalized as not having smoked any cigarettes, even a puff, or used other tobacco in the last 30 days.

7 day point prevalence of abstinence at 6 months,operationalized as not having smoked any cigarettes, even a puff, or used other tobacco in the last 30 days