Friendly competition. Real progress.

Challenge your friends.

Turn steps, recorded walks and runs, workouts and golf rounds into friendly competitions. Follow the standings, save your rivals and go again.

Android · Early access

Ready for your next challenge.

Download the signed Android installer directly from this website. Android 9 or later is required. Health competitions need Health Connect and a compatible activity source.

Download for Android

Version 1.0 · Build 4 · Released September 30, 2026

This is an early-access release. Installation and automated checks passed. Full health-sync testing on physical phones is still in progress.

iPhone & Apple Watch

App Store release in preparation.

The iPhone build is being prepared for review. An App Store download will appear here once it is available.

Already have Challenge installed? Open an invitation link or enter its code in the app to join.

Contact Challenge support

Install on Android

Tap Download for Android on your phone, then open the downloaded file.
If Android asks, allow this browser to install apps, then choose Install. You can turn that permission off again afterward. Keep Play Protect enabled.
Open Challenge and use Google or your email to sign in. Use the same account as before to find your existing profile.
Open Profile to review Health Connect access. Grant the activity categories needed for your competitions.

Coming from a test build? An older debug-signed copy may not accept this installer as an update. Finish any active competition before changing installations, because a challenge can be tied to one phone installation. Contact support if Android says the app conflicts with an installed package. Do not clear app data during an active competition.

Future updates

Return to this page for the latest download. Install it over this signed release to keep your app data. Website downloads do not receive automatic updates from Google Play.

Verify your download

The installer is signed by David Barron. Its version, file size, SHA-256 checksum and signing-certificate fingerprint are available in the release record.