Privacy Policy

Last updated 15 June 2026

Black Water Tek is operated by Spherify Pty Ltd (Australia). This policy covers DTS Gas Guru and DTS v3.0 Dive To Survive ("the apps"). Questions: hello@blackwatertek.com.

The short version

The apps are local-first. Your dive plans, profiles and gear live on your device. You can use the planner fully without an account. If you create an account, we store the minimum needed to sign you in and, if you choose, to sync your data between devices.

What we collect

• Account: your email address and a one-way hash of your password. We never store your password in readable form.
• Two-factor (optional): if you enable it, an encrypted authenticator secret and hashed one-time recovery codes.
• Synced dive data (optional): dive logs, profiles and settings you choose to sync are stored end-to-end encrypted. They are encrypted on your device with a key derived from your passphrase before they reach us, so we cannot read them. Because this encryption is zero-knowledge, if you lose your passphrase and your recovery codes neither we, Apple nor Google can recover your synced data, and it is permanently lost. Data stored locally on your device is unaffected.
• Payments: handled by Stripe. We never see or store your card details; we keep only a customer reference and your subscription status.
• Basic operational logs: standard request logs needed to run and secure the service.

Where it is stored

Account data and encrypted blobs are stored on Cloudflare (D1 and R2). We do not sell your data or share it with advertisers.

Cookies and local storage

The apps use device local storage to keep your plans and a session token so you stay signed in. We do not use third-party advertising or tracking cookies.

Your choices

• Use the planner without an account at any time.
• Export or delete your local data on your device.
• Request deletion of your account and any synced data by emailing us.

Children

The apps are intended for certified divers and are not directed at children under 16.

Changes

We will update this page when our practices change and revise the date above.

Contact

Spherify Pty Ltd, trading as Black Water Tek. Email hello@blackwatertek.com.