MyHeart Counts

Name: MyHeart Counts
Author: Stanford University

Stanford University

CLINICAL GRADE

Validated in clinical trials · Supported by multiple studies

For:Researchers & AcademicsGeneral Public & EnthusiastsPatients & Caregivers

Free

Download on the App Store

App Summary

MyHeart Counts is a research app that helps individuals track their physical activity, estimate cardiovascular risk, and assess functional capacity with a 6-minute walk test. A randomized crossover trial substudy (N=2,458) found that personalized e-coaching prompts, tailored to an individual's baseline activity, significantly increased their mean daily step count. The authors conclude that digital interventions are more effective for increasing short-term physical activity when prompts are personalized.

App Screenshots

Detailed Description

Functionality & Mechanism

Developed by Stanford Medicine, MyHeart Counts functions as a cardiovascular health research platform. The app leverages smartphone sensors to passively collect physical activity and sleep data. Participants actively contribute through health questionnaires, a guided six-minute walk test to assess functional capacity, and by inputting lipid and blood pressure values. The system then calculates a 10-year cardiovascular risk score and a corresponding "heart age," providing personalized feedback and testing various digital coaching interventions.

Evidence & Research Context

A large-scale feasibility study (N=48,968) demonstrated the app is a viable platform for collecting real-world cardiovascular health data, though sustained participant engagement and data completion were identified as challenges.
In a randomized crossover substudy (N=2,458), personalized e-coaching prompts significantly increased short-term physical activity (+402 steps/day) more effectively than generic prompts or standard educational content.
Analysis of over 30,000 remotely collected six-minute walk tests (N=8,922 participants) validated associations between test distance and clinical variables, including diagnoses of atrial fibrillation and peripheral artery disease.
In a longitudinal subset of participants (N=1,129), sustained app use was associated with a statistically significant increase in six-minute walk test distance (+17.5 m).
The app has been utilized as a data collection tool in multiple studies, generating a large, publicly available dataset for cardiovascular research.

Intended Use & Scope

Primarily designed for researchers to conduct large-scale observational and interventional cardiovascular studies. The app also serves the general public as a tool for self-monitoring and health education. The risk scores provided are for informational purposes only and do not constitute a clinical diagnosis. Users should consult a healthcare professional for medical advice and management of cardiovascular risk.

Studies & Publications

4 publications

Peer-reviewed research associated with this app.

Effectiveness/Outcome Study

Unlocking insights: Clinical associations from the largest 6-minute walk test collection via the my Heart Counts Cardiovascular Health Study, a fully digital smartphone platform

Kim et al. (2025) · Progress in Cardiovascular Diseases

Validated known health associations and identified new clinical patterns using data from over 30,000 smartphone-based walk tests.

The six-minute walk test (6MWT) is a prognostic sub-maximal exercise test used clinically as a measure of functional capacity. With the emergence of advanced sensors, 6MWTs are being performed remotely via smartphones and other devices. The My Heart Counts Cardiovascular Health Study is a smartphone application that serves as a digital platform for studies of human cardiovascular health, and has been used to perform 30,475 6MWTs on 8922 unique

RCT

Personalized digital behavior interventions increase short-term physical activity: a randomized control crossover trial substudy of the MyHeart Counts Cardiovascular Health Study

Javed et al. (2023) · European Heart Journal - Digital Health

Personalized coaching increased daily steps by 402 and hourly standing reminders increased steps by 292.

AimsPhysical activity is associated with decreased incidence of the chronic diseases associated with aging. We previously demonstrated that digital interventions delivered through a smartphone app can increase short-term physical activity.Methods and resultsWe offered enrolment to community-living iPhone-using adults aged ≥18 years in the USA, UK, and Hong Kong who downloaded the MyHeart Counts app. After completion of a 1-week baseline period,

In the Media

Smartphones could be game-changing tool for cardiovascular research

Stanford researchers launched MyHeart Counts to transform cardiovascular research by using smartphones to provide rapid, large-scale and real-time measurement of individuals' physical activity. Within six months of the app's launch, researchers had enrolled 47,109 participants from all 50 states who consented to participate in the study using Apple's ResearchKit framework. The app collected data from 4,990 participants who completed a six-minute walk fitness test using built-in motion sensors, achieving numbers several times larger than the largest study previously published.

STANFORDRead article

Stanford's heart health app launches in Hong Kong and UK

Stanford University School of Medicine developed MyHeart Counts to enable users to learn about their heart health while participating in a large-scale cardiovascular study, using Apple's ResearchKit framework and iPhone motion sensors to collect physical activity data. "We are ready to take the study as far as it will go. We would like to build a new Framingham heart study for the ages," said Euan Ashley, professor of cardiovascular medicine at Stanford, noting they want millions of participants. The app has expanded to Hong Kong and the UK with over 41,000 users already participating in the study.

STANFORDRead article

Stanford launches smartphone app to study heart health

Stanford University School of Medicine researchers launched MyHeart Counts to study heart disease prevention and treatment, using Apple's new ResearchKit framework to collect data about physical activity and cardiac risk factors. "We are looking for everyone who is curious as to how healthy their heart is to download this app," said Dr. Alan Yeung, noting that users can see their activity levels and 'heart age.' The app launched March 9, 2015, and aims to provide data for the largest study of measured physical activity and cardiovascular health to date.

STANFORDRead article