Support

Last updated: May 14, 2026

Need help with Duro? We read every message. The fastest way to reach us is email — write to support@trainduro.com and we'll reply within 1-2 business days.

Before emailing, check the answers below — most questions are covered.

Subscription and billing

How do I start the 7-day free trial?

Open Duro, complete onboarding, and tap "Start Your Free Trial" on the paywall screen. You'll need an Apple ID with a valid payment method on file. You won't be charged until day 7 — cancel before then to pay nothing.

How do I cancel my subscription?

On your iPhone: open the Settings app → tap your name at the top → tap Subscriptions → tap Duro → Cancel Subscription. Cancellation takes effect at the end of your current billing period.

If you cancel during the free trial, you keep access until day 7 and are not charged.

How do I restore my purchase on a new device?

Open Duro on the new device, go to the paywall screen, and tap Restore at the bottom. Make sure you're signed into the same Apple ID you used to purchase.

Why was I charged?

Duro Pro is an auto-renewing subscription. If you didn't cancel before the trial ended (or before the renewal date), Apple charges your payment method automatically. To stop future charges, cancel the subscription in your Apple ID settings (see above).

For refund requests, Apple handles all in-app purchase refunds. Visit reportaproblem.apple.com and select your Duro purchase.

What does Duro Pro include?

Everything: workout tracking, Growth Zones, recovery insights, strength tracking, the workout builder, import and export, and coaching features. There is no free tier beyond the trial.

Your data

Where is my workout data stored?

On your device. Duro uses Apple's local on-device database (SwiftData). Your workouts, templates, custom exercises, and history never leave your iPhone unless you use the AI coaching features or you export them yourself.

How do I export my workout history?

Open Duro → Settings → scroll to Data → tap Export Workout History. Duro generates a CSV file that you can share via email, save to Files, or send to another app.

How do I import workouts from Strong or Hevy?

Export a CSV from your old app (both Strong and Hevy support CSV export). Open Duro → Settings → Import Workout History → choose the file. Duro maps exercises automatically and shows you anything it can't match.

How do I delete all my data?

Uninstalling Duro removes all on-device data. If you've used AI coaching, contact us at privacy@trainduro.com to request deletion of any server-side data.

Using Duro

What are Growth Zones?

Growth Zones show how many sets per muscle group you trained this week, against research-based volume thresholds — minimum effective volume (MEV), maximum adaptive volume (MAV), and maximum recoverable volume (MRV). You see at a glance which muscles are in the growth zone, which are maintaining, and which need more (or less) work.

How does the workout builder work?

Pick a split (push/pull/legs, upper/lower, full body, etc.) and Duro generates a session matched to your current volume gaps. You can edit any exercise, swap muscle groups, or build from scratch.

Why is Duro only on iOS?

We're a small team and chose to build the best possible hypertrophy tracker for one platform first. Android is not on our roadmap right now.

What if I miss a workout?

Nothing breaks. Duro doesn't punish missed days. Your Growth Zones will reflect the lower weekly volume — pick up where you left off whenever you're back in the gym.

Troubleshooting

The app crashed

Sorry about that. Duro automatically sends anonymous crash reports to our servers so we can fix the issue. If you can reproduce the crash reliably, email support@trainduro.com with steps and we'll prioritize a fix.

The paywall keeps appearing after I subscribed

Tap Restore on the paywall. If that doesn't work: make sure you're signed into the same Apple ID that purchased the subscription. As a last resort, restart your iPhone and try again — sometimes Apple's servers take a few minutes to sync purchases.

My workout didn't save

Duro saves continuously while you train, even with no internet. If a workout truly disappeared, please email us with the date and a description — we may be able to recover it from crash logs.

A specific exercise is missing from the library

You can create custom exercises from the exercise picker — tap the + button at the top right. If you think an exercise should be in the default library, let us know and we'll consider adding it.

Still need help?

Email us at support@trainduro.com. Include your iPhone model, iOS version, and a description of what happened (with screenshots if you can). We reply within 1-2 business days.

For privacy questions, GDPR or data protection requests, write to privacy@trainduro.com.

Attributions

Exercise illustrations in Duro are sourced from the Everkinetic open data project by Greg Priday, used under the Creative Commons Attribution-ShareAlike 4.0 International License (CC-BY-SA 4.0). Some images have been resized or recolored for use in Duro.