Undertow measures how much of each crypto asset actually sits in exchange wallets — and tells you when that changes.
Nobody opens an app to scan tables. Unusual moves arrive as a notification with the numbers already in it.
Balances read directly from six blockchains every 10 minutes. Nothing licensed from a third party.
No signals, no scores, no price targets. Every number is a historical measurement you can verify.
No wallet connection. No location. No advertising ID — we don't even ask for tracking permission.
A rising exchange balance can mean coins arrived to be sold — or that an institution moved custody. We show the measurement and the context, and leave the call to you.
24h / 7d / 30d change, ranked and z-scored against each asset's own history.
Total stablecoins on exchanges — the one on-chain metric with no interpretation ambiguity.
Classified, with internal rotations and bridge movements filtered out.
Funding, open interest, basis and live liquidations.
Undertow is an information and data-visualisation tool. It does not provide investment advice or buy/sell recommendations. Crypto assets are high risk and you may lose the entire amount you invest.
Last updated: 28 July 2026 · Controller: ST Matrix · destek@stmatrix.com.tr
Undertow collects the minimum data needed to work. Location, contacts, camera, microphone, wallet addresses and advertising identifiers are never collected. No ads. Your data is never sold or shared for marketing. This is not a marketing claim but a security decision: data not collected cannot leak.
| Data | Purpose | Legal basis |
|---|---|---|
| Email address | To identify your account | Performance of contract |
Provider ID (sub) | Matching your Google/Apple account | Performance of contract |
| Watchlist, alert rules | Core product function | Performance of contract |
| Push token | Delivering notifications | Consent |
| Language, theme, timezone | Showing the app as you prefer | Performance of contract |
| Anonymous usage events | Product improvement (opt-out) | Legitimate interest |
If you hide your email when signing in with Apple, we only ever receive a
@privaterelay.appleid.com address and never see your real one.
Sign-in, sign-out, account deletion and suspicious access attempts are logged. Your IP address is never stored in plain text — only an irreversible HMAC-SHA256 hash, generated with a key that rotates daily, so records from different days cannot be correlated.
Your data is never sold, rented or shared for marketing. Infrastructure providers required to run the service:
| Provider | Purpose | What it sees |
|---|---|---|
| Hetzner (Germany) | Server hosting | Encrypted database |
| Cloudflare | Routing and security | IP address (not stored by us) |
| Expo / Apple / Google | Notification delivery | Push token, notification text |
| RevenueCat | Subscription validation | Anonymous user ID, purchase state |
| Data | Period |
|---|---|
| Account data | While the account is active |
| Email address after deletion | Erased immediately |
| Account record after deletion | 30 days, then fully removed |
| Security logs | 180 days (critical events 400 days) |
| Notification logs | 90 days |
| Subscription records | Retained as required by financial regulation |
Under GDPR and Turkish KVKK you may:
Requests: destek@stmatrix.com.tr (answered within 30 days)
Important: deleting your account does not cancel your subscription. Cancel it separately in your App Store or Google Play account settings.
In the event of a breach, authorities are notified within 72 hours and affected users are informed.
Undertow is not directed at users under 17 and does not knowingly collect data from them.
Our servers are in Germany (EU). Apple, Google and Cloudflare services may transfer data outside the EU under standard contractual clauses.
We notify you in-app if this policy changes, and ask for renewed consent for material changes.
ST Matrix · destek@stmatrix.com.tr · stmatrix.com.tr
Last updated: 28 July 2026 · Provider: ST Matrix · destek@stmatrix.com.tr
Undertow is an information application that measures and visualises how much of each crypto asset sits on exchanges, derivatives-market indicators and large on-chain transfers. Data is collected from public blockchain records and exchanges' public APIs.
Undertow does not provide investment advice, financial advisory services, or buy and sell recommendations. All figures shown are historical measurements; past data does not predict future price movements. No indicator, badge, ranking or notification in the app should be read as a recommendation to buy or sell. Crypto assets are high risk and you may lose the entire amount you invest. All investment decisions and their outcomes are entirely yours.
We take data quality seriously — addresses are verified on-chain, abnormal values are withheld from publication, and data gaps are shown openly rather than hidden (Settings → Methodology). Nevertheless:
The service is provided "as is" with no warranty of uninterrupted or error-free operation.
Refunds are subject to Apple and Google policies and are requested directly from the relevant store.
Deleting your account does not cancel your subscription. You must cancel it separately in your store account settings.
You may not:
The design, code, brand and the derived data sets we produce belong to ST Matrix. You are granted a licence for personal, non-commercial use.
Blockchain data itself is public and owned by no one; what we own is our method of collecting, verifying and processing it, and the historical data set we have built.
To the maximum extent permitted by law, ST Matrix is not liable for any direct or indirect loss arising from use of the service, including investment losses. Total liability may not exceed the subscription fees paid in the last 12 months. This limitation does not apply to intent or gross negligence.
We reserve the right to improve, change or discontinue the service. On discontinuation, active subscribers receive reasonable notice and are directed to the store's refund process for any unused period.
These terms are governed by the laws of the Republic of Türkiye. The courts of Istanbul have jurisdiction. Your statutory consumer rights are reserved.
ST Matrix · destek@stmatrix.com.tr · stmatrix.com.tr