Big Stack privacy policy

Last updated 8 November 2026

On your watch

Big Stack reads activity, health and sensor history on your watch to show it on the face. None of that leaves the watch.

Network use

Only when you pick the Custom theme does Big Stack contact KiezelPay (api.kiezelpay.com, through your phone) to get an unlock code and check the purchase. It sends the watch's unique device ID and model number, nothing else: no name, email, location, health or activity data. If you never pick Custom, it makes no network requests.

Payment

Payment is handled by KiezelPay on www.kzl.io/code, under KiezelPay's own privacy policy. We never see your card or PayPal details.

Sharing

We don't sell or share any data. We don't receive any data about you beyond what KiezelPay reports for a purchase (the device ID and the payment).

This website

No cookies, no analytics, no tracking.

Changes and contact

If this policy changes, this page is updated first. Questions: see Big Stack support.