Data protection you can explain in one sentence
People who book an appointment often share sensitive things: a photo of their skin, the reason for therapy, a phone number. Rather than building in every tracking tool imaginable, Zytfenster cares about one thing above all: that the people who book with you feel they’re in good hands. That’s why it stores as little as possible, for as short a time as possible, and only where it’s installed.
This page explains how Zytfenster handles data as a booking tool. You’ll find the privacy policy for this website here (in German).
“Bookings are kept on a server in Switzerland, photos are encrypted and deleted after the appointment, and there’s no tracking.”
Applies if the hosting is in Switzerland.Who has the data
Installed yourself
The data is on your hosting, and only there. I have no access, see no data and don’t even know your installation exists. Zytfenster never contacts me, whether for updates, statistics or error reports.
Hosted by me
The data is on my hosting with cyon AG in Basel, on servers in Switzerland. I only process it on your behalf. Our data processing agreement (DPA) sets this out.
What is stored, and for how long
| Data | When | How long |
|---|---|---|
| Name and email | with every booking | 12 months after the appointment, then removed automatically |
| Phone number and message | only if the person provides them | 12 months, then removed |
| Answers to custom questions | only if you add questions | 12 months, then removed |
| Photo | only for services with a photo | 7, 14, 30 or 90 days after the appointment, 30 by default. You can delete it straight away at any time. |
| Appointment: service, date, time | with every booking | without personal details, until you delete it |
| Busy times from your calendars | every 10 minutes | start and end only, replaced continuously |
| Hash of the IP address, irreversible | to prevent misuse | 1 day |
| Email log with shortened address | with every email sent | 30 days |
| Database backup, without photos | daily | 14 days |
If you delete your account, Zytfenster deletes all bookings and photos immediately. Bookings remain in its own backups for 14 days at most, plus any backups your hosting makes.
What Zytfenster deliberately leaves out
Tracking and advertising cookies
The booking page sets no cookies at all. The admin area sets one, purely for signing in.
Third-party servers
Fonts, scripts and images come from your own hosting. No analytics, advertising or AI service is connected.
Photos in your inbox
You only see photos in the admin area. The email simply says: “A photo is attached.” (“Ein Foto ist dabei.”)
Photos in backups
A deleted photo is gone. If your hosting makes its own backups, photos are only stored there in encrypted form.
The contents of your private calendars
Zytfenster reads when you’re busy, not what the entry says.
More details than needed
The form only asks for name and email. Phone number and message are optional.
Where data still goes
Some connection to the outside world is unavoidable. These are the routes, and you decide on each one.
Emails
The confirmation goes to the person who books. The notification of a new booking goes to you, without client details if you prefer. Emails are only as secure as the inbox they land in. Tip: use an address with a Swiss provider for your practice.
Calendars you connect
Zytfenster fetches them from iCloud, Google or Outlook. None of your bookings leave in the process.
The “Zytfenster” calendar
If you subscribe to it in Google or iCloud, that provider reads your appointments. The default is “Zytfenster appointment” (“Termin Zytfenster”), with no names. If you choose the detailed version, the provider sees the name, service, email and phone number.
The “Google Calendar” (“Google Kalender”) button
Only people who click it after booking send their appointment to Google.
Video links
For online appointments, you add the link to your video service, for example Zoom or Teams. The call is subject to that service’s rules.
Hosting logs
Every hosting provider logs requests with IP address and time. The hosting provider decides how long they’re kept.
How Zytfenster protects the data
Photos
The browser scales them down. The server saves them afresh, which strips out location and camera data. They’re only ever stored encrypted, with AES-256.
Data outside the web folder
The database, photos and logs sit in a folder that can’t be reached from the internet.
Signing in with a link
The link is valid for 15 minutes and works only once. Zytfenster stores links and sessions only as a hash. Anyone who steals the database can’t use it to sign in.
Protection against misuse
A limited number of bookings and sign-in attempts per hour, a spam trap in the form, a daily limit for emails.
Automatic deletion
Photos after the set period, contact details after 12 months, logs after 30 days, backups after 14 days. The cron job takes care of it, so nobody has to remember.
Checks and updates
I’ve systematically checked the code for security vulnerabilities, with the help of AI, and fixed all critical findings. An independent review by a specialist is planned. Updates are free.
Limits you should know about
Whoever runs the server can technically read everything
That includes the photos, because the key is on the same server. Encryption protects against stolen files and backups, not against a hijacked hosting account. So choose hosting you trust, and protect access with two-factor authentication.
Your email inbox is the key to the admin area
There’s no password that could be guessed or turn up in a data leak. On the other hand, anyone who controls your inbox can sign in. Keep it well protected.
You remain responsible
Zytfenster helps with this, but it’s no substitute for advice from a data protection specialist.
Ready-made texts for your own website
A section for your website’s privacy policy, matched to your settings, and a template for the data processing agreement. Plus information requests and deletion per person at the click of a button.
By the way, this website doesn’t set any cookies either, and loads nothing from third-party servers.
