Terms and Conditions

Last updated 4 October 2026

These terms apply to the Pen Marks app made by Hayde Tech Ltd ("we"). By using the app you agree to them. Your use is also governed by Apple's Licensed Application End User License Agreement.

Not medical advice

Pen Marks shows published reference growth charts (such as CDC and WHO) for information only. It does not diagnose, treat or give medical advice. Always talk to a qualified health professional about your child's growth and health. Do not delay seeking advice because of anything shown in the app.

Free use and the lifetime unlock

Some features are free. A one-time in-app purchase unlocks further features for the life of the app on devices signed in with your Apple ID. Purchases, prices, payment and refunds are handled by Apple under its terms. Features may change in future versions.

Your data

You are responsible for the information you enter and for keeping backups. Data is stored on your device and, if you choose, in your own iCloud account. See our Privacy Policy.

Acceptable use

Do not reverse engineer, resell or misuse the app, or use it unlawfully.

Liability

The app is provided "as is". To the extent the law allows, we are not liable for indirect or consequential loss, or for loss of data. Nothing in these terms limits liability that cannot be limited by law, or your statutory rights as a consumer.

Changes

We may update these terms. We will post changes here and update the date above.

Law

These terms are governed by the laws of England and Wales. If you live elsewhere you keep the protections of your local consumer law.

Contact

Hayde Tech Ltd · support@haydetech.com