Support
Get help with the app
Cardio Protocol is a multi-protocol training timer for iPhone and Apple Watch. If something isn't working right, or you have a question or suggestion, reach out below — a real person reads every message.
Running into something specific — heart rate not showing, a session that didn't save, coaching not speaking? See the Troubleshooting guide for fixes to the most common issues.
Frequently asked questions
Which protocol should I start with?
Each protocol has its own explainer screen in the app covering what it is, why it works, and what to expect — open any protocol from the picker to read it before you start. If you're not sure, Zone 2 and 12-3-30 are the gentlest starting points; Norwegian 4x4 and Tabata are more intense.
Do I need an Apple Watch to use the app?
No — the iPhone app works fully on its own. The Apple Watch app is an optional companion that mirrors your live session and lets you start or stop from your wrist.
Why does the app ask for Health permissions?
Health access is used to read your live heart rate for zone coaching, and to save completed sessions to Apple Health as workouts if you choose to enable that. You can deny it and still use the app as a plain protocol timer.
Where's my data stored?
Everything stays on your device, in your own Apple Health data, or in your own iCloud account if you enable backup. See the Privacy Policy for full details.
I found a bug or have a feature request.
Email sanjay.almeida@gmail.com with what happened (or what you'd like to see) and, if possible, your iPhone/Watch model and iOS/watchOS version. Screenshots help a lot.
How do I cancel my subscription?
Open the Settings app on your iPhone → tap your name → Subscriptions → Cardio Protocol → Cancel Subscription. Or use the "Manage Subscription" button inside the app's Settings.