Stateless Architecture
SwimST has no server accounts, no login, and no cloud sync. All data lives locally on your device in an encrypted SQLite database. This ensures total privacy, offline access, and zero subscription fees.
The tradeoff: you are responsible for your own backups. If you lose your device or reinstall the app, data is gone — unless you set up a Recovery Link.
Legal Disclaimer — Sensitive Data: You must not include sensitive personal data — such as full legal names, dates of birth, medical information, or any other personally identifiable information (PII) — in session names, athlete labels, exercise descriptions, or any other content transmitted via shared or recovery links. Any data you choose to include is transmitted at your sole risk and responsibility. To the maximum extent permitted by applicable law, Otenz disclaims all liability for any claims, damages, or legal consequences arising from the content you share. By using these features you acknowledge and accept these terms. See our Terms of Service and Privacy Policy for full details.
The Recovery Link
A Recovery Link is a special encrypted URL that contains all your data: every athlete, every session, every setting. It auto-updates every time you save or modify a session.
How it works
SwimST exports a full backup (athletes, sessions, exercises, tools, pool lengths)
The backup is encrypted with AES-256-GCM — only you have the key
The encrypted blob is uploaded to web.swimst.app
The decryption key lives in the URL fragment (#key=...) — the server never sees it
Opening the link on any device downloads and decrypts the backup
| Encryption | AES-256-GCM (military-grade) |
| Server knowledge | Zero — only stores encrypted bytes |
| Auto-update | Every session save/edit/delete |
| Expiry | 90 days after last update (auto-renewed) |
| Cost | Free |
Optimized Coach Workflow
Initial Setup (5 minutes)
Open SwimST → Preferences (gear icon)
Enter your name and select Coach role
Go to My Recovery and generate a Recovery Link
Bookmark the link — or email it to yourself
Daily Workflow
Create sessions and assign them to athletes as usual
The Recovery Link updates automatically after every save
No manual backup steps needed
Sharing with Athletes
Go to the My Recovery page
Tap Generate Link for a specific athlete
Send the link to the athlete (WhatsApp, email, etc.)
The athlete opens the link → data imports automatically
Future updates sync automatically
Moving to a New Device
Install SwimST on the new device
Open your Recovery Link from your bookmarks
SwimST detects an empty database and auto-imports everything
Generate a new Recovery Link on the new device
Season Reset
At the start of a new season, go to My Recovery → Data Management:
Reset Sessions — removes all sessions, keeps athletes
Reset Athletes — removes all athletes and sessions
Factory Reset — starts fresh (shared links preserved)
Before resetting, make sure your Recovery Link is up to date.
Shared Browser (Web App)
If multiple coaches or athletes use web.swimst.app on the same device, the browser can only hold one user's data. On startup, SwimST shows a dialog with three options:
Continue — keep the current data and work normally
Clear Data — remove sessions and athletes but keep preferences and saved links
Full Reset — erase everything and start from scratch
If a Recovery Link exists, a Copy Recovery Link button lets you save the backup before clearing
Each user should bookmark their Recovery Link. Switching users becomes: copy link → clear/reset → open your own link.