Privacy policy
Short version: we built Napkin so that we can't read what you write. No accounts, no cookies, no ads, no trackers.
Effective 1 October 2026
Who runs Napkin
Napkin (napkin.deal and the Napkin Android app) is made by Cindy Kate, an independent developer in the European Union, who is the controller of the data described here. Contact: napkin.deal.official@gmail.com.
What you write on a napkin
- Your napkin text and its title are encrypted on your device before they are sent (AES-GCM). The key is part of the link after the # sign. Browsers never send that part to a server, so our server never has the key and cannot read your napkin.
- The server keeps only the encrypted napkins, padded to the same size so their length reveals nothing, plus random access codes (stored only as hashes) that decide who may take part.
- Everything about a napkin is deleted from the server 24 hours after it was created.
What stays on your device
- Links you started or answered, and the access codes that belong to them, so you can return to a napkin.
- Opened napkins you keep under "Your napkins". They are stored only on your device, encrypted with a key that cannot be copied out of it. We never receive them. If you lose the device or clear the app's data, they are gone, unless you exported them.
- An export file, if you make one, is not encrypted. Where you keep it is up to you.
- Your language choice.
All of this is needed for Napkin to work, and you can delete it at any time by deleting napkins in the app or clearing the app's (or website's) data.
Anonymous statistics
To know whether Napkin is useful, our server counts things like page visits, demos played and napkins completed. For each count, the device sends only the page or event name, for example "napkin created", plus the name of the website that linked to Napkin, if any. Nothing is stored on your device for this. We never receive the napkin text, the title, your name or any identifier.
To count daily visitors without tracking anyone, the server combines your IP address and browser type with a random value that is replaced every day, turns that into a short scrambled code, and keeps only the code, for that day only. IP addresses are not stored. Visitors can't be recognised across days. The counts are kept for 90 days.
Abuse protection
To stop anyone creating napkins in bulk, the server holds the IP addresses that created napkins in memory for up to one hour. They are not written to disk or logs, and they disappear after the hour or when the server restarts.
Why we may do this (legal basis)
- Running your napkins (storing the encrypted napkin, the access codes, the 24-hour deletion): this is the service you ask for, so it rests on Art. 6(1)(b) GDPR.
- Anonymous statistics and the daily visitor count: our legitimate interest in knowing whether Napkin is used and works, Art. 6(1)(f) GDPR. We keep it to the minimum: no identifiers, a code that changes every day, nothing stored on your device.
- Abuse protection: our legitimate interest in keeping Napkin available and stopping bulk misuse, Art. 6(1)(f) GDPR, for one hour and in memory only.
No cookies, ads or third parties
- No cookies, no advertising, no analytics services, no social-media trackers.
- Fonts and all other files come from our own server. Your device does not contact Google or anyone else when you use Napkin.
- We do not keep access logs of requests.
- The server is rented from Hetzner Online GmbH in Germany, which processes data only on our behalf under a data processing agreement (Art. 28 GDPR). Data is not transferred outside the European Union.
Sharing links
When you share a napkin link through a messenger or email, that service sees the link like any other message, including the key part. Share links only with the person you are negotiating with.
Children
Napkin is not directed at children under 16.
Your rights
Under the GDPR you may ask what data we hold about you, ask us to correct or delete it, and object to processing based on our legitimate interest. Because we don't know who you are and can't read napkins, there is usually nothing we can link to you. Write to napkin.deal.official@gmail.com and we will answer within one month, as far as we technically can. You may also complain to your data protection authority.
Changes
If this policy changes, the new version appears here with a new date. If paid features arrive later, this page will describe what the payment provider receives before anything is charged.