The Institute for International Internet Interventions for Health (i4Health) at Palo Alto University proposes to develop digital tools specifically designed to help low income English-speaking and Spanish-speaking smokers to quit. The investigators aim to test whether a mobile-based digital intervention designed with systematic input from low-income English- and Spanish-speaking smokers from a public sector health care system can significantly improve its acceptability, utilization, and effectiveness. Using human-centered development methods, the project will involve low-income patients of the San Francisco Health Network in the design of a web app/text messaging tool. The investigators will also use participants input to improve the recruitment and dissemination strategies. i4Health will join forces with the Center for Behavioral Intervention Technologies (CBITs) at Northwestern University to iteratively develop successive versions of the digital interventions informed by our human-centered approach.

The full study involves 4 successive outcome studies testing the effectiveness of the Stop Smoking San Francisco web app.

The first three are single-group non-randomized pre-post studies with 1, 2, and 3-month follow-ups. These will test gradually improved versions of the app.

The fourth study will involve a randomized trial comparing the initial version (the baseline version) of the web app to the final version of the web app, to determine if the final version is significantly better than the baseline version in terms of increased utilization and abstinence rates.

To join this study, go to: https://stopsmokingsf.org

The project involves three specific aims:

Specific Aim #1: Human-centered development of an English/Spanish smoking cessation web app. The investigators will develop iterative versions of a digital smoking cessation tool (a web app with text messaging components) that is highly responsive to the needs and preferences of low-income English- and Spanish-speaking smokers. Development will take place with systematic input from patients who are part of the San Francisco Health Network (SFHN). The SFHN serves 70,000 members, most of whom are low-income individuals.

Specific Aim #2: Improvement of dissemination strategies. Input from SFHN patients will identify effective ways of reaching and encouraging low-income English- and Spanish-speaking smokers to use the digital smoking cessation interventions to be developed. This information will support ongoing dissemination and implementation efforts beyond the grant period.

Specific Aim #3: Evaluation of resulting smoking cessation web app. Researchers will evaluate the effectiveness of the successive versions of the resulting stop smoking web app by recruiting smokers at two levels: a) within the SFHN, and b) throughout the state of California, culminating with an online randomized controlled trial. Increased effectiveness will be defined as 1) increased utilization of the web app and 2) higher abstinence rates than those obtained by a baseline "usual care" web app.

Inclusion Criteria:

• English speaking (ES) and Spanish speaking (SS)

Exclusion Criteria:

• Not a smoker