Privacy

Your books are yours.

Vesper has no accounts and never sees your books. This page says what leaves your Mac or iPhone, where it goes, and how to turn it off.

Last updated on 7 October 2026. It covers Vesper for Mac, Vesper for iPhone, this website and vesper.press.

Your books

A book in Vesper is a folder of files on your Mac, in the place you chose. Vesper reads and writes them there, and nowhere else.

With Vesper Pro, your books sync between your Mac and iPhone through your own iCloud account, in your private iCloud database. They travel between Apple’s servers and your devices. We can’t read them, and neither can anyone else you haven’t shared them with. Apple’s privacy policy covers iCloud.

Anonymous usage data

To learn which parts of Vesper writers use, the apps send a few anonymous signals to TelemetryDeck, an analytics service from Germany. A signal says, for example, that a book was opened, that a chapter version was saved, or that a writing session ended, with how long it lasted and how many words it added or removed. Most signals are sent at most once a day.

Signals also carry whether you have Vesper Pro, and technical facts such as the app’s and the system’s version, the kind of device, and your language and region. They never contain your words, your books’ or chapters’ titles, or file names.

Each signal carries an identifier that is scrambled on your device before it’s sent, and scrambled again by TelemetryDeck, so it can’t be traced back to you. With Vesper Pro, the identifier is derived from your iCloud account the same way, so your Mac and your iPhone count as one writer. Your iCloud account itself never leaves your device.

To turn it off on the Mac, go to Vesper ▸ Settings ▸ Privacy and switch off “Share anonymous usage data”. On the iPhone, open the Settings app, go to Apps ▸ Vesper and switch off “Share Anonymous Usage Data”. Nothing more is sent from then on.

Crash reports

When Vesper crashes or freezes, it sends a report to Better Stack, an error-tracking service whose servers for these reports are in the United States. A report says where in Vesper the problem happened: the code that was running, the kind of error, the app’s and the system’s version, and the kind of device.

Before a report leaves your device, Vesper removes file paths and names, anything in quotation marks, and your computer’s name. Reports never contain your words, screenshots, or a record of what you did before the crash.

To turn them off on the Mac, go to Vesper ▸ Settings ▸ Privacy and switch off “Send crash reports”. On the iPhone, open the Settings app, go to Apps ▸ Vesper and switch off “Send Crash Reports”.

Buying Vesper Pro

Vesper Pro is a subscription you buy through the App Store. Apple handles the payment and your Apple Account; we never see your name, your email address or your payment details. The apps check with Apple, on your device, whether your subscription is active.

Sharing a reading copy

When you share a book, Vesper puts a copy of the chapters you chose in a separate area of your iCloud, and Apple makes it readable to anyone who has its link. The link holds the book’s title and a key after the “#” sign. Browsers keep that part to themselves, so vesper.press never receives the title or the key.

When you stop sharing, the copy is deleted from your iCloud and the link stops working for everyone. Reading a book someone shared with you needs Vesper and an iCloud account.

AI

Only if you use Vesper’s AI features, which come with Pro with AI, and only after you’ve agreed to what they send.

When you ask the AI for something, such as rewriting a passage, continuing a chapter, revising it, or answering a question about your book, Vesper sends what that task needs: the passage or the chapter, and the parts of your book you allowed it to use, such as wiki entries, your plot, and your voice sample. It goes to Vesper’s relay, a server we run in Nuremberg, Germany, which passes it to Anthropic or OpenAI and sends their answer back to you.

The relay never stores your text. Anthropic and OpenAI don’t train their models on it, and keep it only as long as their safety checks require. They receive it under an anonymous identifier, so they can stop misuse without knowing who you are.

To count each week’s Vesper Credits, the relay keeps your subscription’s App Store transaction number, your plan and its status, which it confirms with Apple, and for each request the model that answered, how much it used, and when. Your AI settings, such as that you agreed and which models you prefer, sync between your devices through your iCloud.

This website and vesper.press

Neither site uses cookies, analytics or trackers. Anything you type on this page stays in your browser and is gone when you leave. Like every website, they are delivered by hosting services, writewithvesper.com by Cloudflare and vesper.press by GitHub, which process your IP address to send you the page.

Your rights

You can ask us what we hold about you, and have it corrected or deleted. You can object to how we use it, and you can complain to a data protection authority. Because Vesper has no accounts, and the relay keeps only the subscription records above, there is usually nothing about you for us to look up, but write to us and we’ll help.

We use the anonymous usage data and the crash reports in our legitimate interest in making Vesper work well (Article 6(1)(f) GDPR), and the AI and sharing data to do what you asked for (Article 6(1)(b) GDPR).

Who we are

Vesper is made by David Joos, [postal address]. Write to [email address] with any question about your privacy.

Changes

If Vesper starts doing anything different with your data, this page will say so first, with a new date at the top.