Privacy

Lucerna collects nothing about you. It has no account, no server of its own, and no analytics of any kind. Nothing you read, open or mark is sent anywhere.

What stays on your device

Lucerna keeps a small amount of state so that a document opens where you left it: the page and scroll position you reached, your zoom, rotation and layout, the pages you bookmarked, the passages you marked, and a list of the documents and folders you opened recently. All of it lives in Lucerna's own folder inside the app's container on your device. It is written by the app and read by the app, and by nothing else.

Your documents

Lucerna reads the PDFs you point it at and never writes to them. Darkening a page is a drawing pass performed while the page is on screen; the file on disk is untouched. The app is sandboxed and holds read-only access to the files and folders you choose yourself.

iCloud

If you keep documents in iCloud Drive, Lucerna can sync your reading positions, bookmarks and marks for those documents between your own devices, through your own iCloud account. This is Apple's iCloud key-value store: Lucerna has no access to it beyond your own devices, and the documents themselves are never copied anywhere. If you would rather it did not, turn it off in Settings.

Handoff

When Lucerna is open on one device, it advertises what you are reading to your other devices over Apple's Continuity, so you can pick the book up where you left it. Apple carries that between devices signed into the same Apple Account; it does not reach us.

Purchases

The unlock is an in-app purchase handled entirely by Apple through StoreKit. Lucerna never sees your payment details, and there is no receipt server of ours for it to talk to. Whether the app is unlocked is answered by asking the App Store on the device.

This website

These pages are static files on Amazon CloudFront. They set no cookies, load nothing from any other host, and carry no analytics and no advertising. One page — the support page — has one small script, served from this same site, which does nothing until you use the form on it. The standard access logs a web server keeps may record your IP address for a short while; nothing else about your visit is recorded.

The support form

The form on the support page exists so that you can write to us without opening a mail client. This is what happens to what you type.

What is sent. Your name, the email address you want a reply at, the optional subject, and your message. Along with them go two things your browser tells every website it talks to: the country it appears to be connecting from, and its user-agent string. That is the whole of it. There is no cookie, no identifier, and no tracking of any kind on that page.

Where it goes. Into one email, sent by Amazon SES from noreply@sp33c.tech to info@sp33c.tech, which is our own inbox. Your address is set as the reply-to, so answering you is a plain reply. The message is not copied to a database, a ticketing system, a spreadsheet or anyone else.

What is kept, and for how long. The message lives in our mailbox for as long as the conversation is useful and is deleted when it stops being — at the outside, two years, and sooner if you ask. Nothing else about the submission is stored. In particular your IP address is never written down: to stop the form being used to send thousands of messages, we keep a keyed hash of it — a number the address cannot be recovered from — beside a counter, and both delete themselves automatically after an hour or a day.

Why we are allowed to. Article 6 (1) (b) GDPR where your message is about a purchase or the app you have, and Article 6 (1) (f) otherwise: we have a legitimate interest in answering people who write to us, and in the anti-abuse counting above, which is the least we could do and still keep the form open.

You do not have to use it. Writing to info@sp33c.tech from your own mail client reaches the same inbox and involves none of the above.

Who else touches any of this

The website and the form run on Amazon Web Services in the eu-central-1 region, Frankfurt — the pages themselves are on CloudFront, which is worldwide by design, and the form's endpoint, its anti-abuse counters and the mail relay are all in Frankfurt. AWS acts as our processor under Article 28 GDPR, on the standard AWS data processing addendum, and does not use any of it for its own purposes. Nobody else is involved: no analytics provider, no support desk, no CRM, no advertising network.

Your rights

Under the GDPR you can ask us for a copy of what we hold about you (Article 15), to correct it (16), to delete it (17), to restrict what we do with it (18), to have it handed over in a portable form (20), and to object to processing we base on legitimate interest (21). In practice, for this site, that comes down to the emails you have sent us, and one message to info@sp33c.tech is enough to have them gone.

You can also complain to a supervisory authority. For us that is the Bayerisches Landesamt für Datenschutzaufsicht, Bavaria being where this is run from; you may equally go to the authority where you live.

Who is responsible

The controller for this website, in the sense of Article 4 (7) GDPR, is the person named in the imprint, at the address given there. There is no data protection officer: one person is well under the threshold that requires one under §38 BDSG, and questions go straight to info@sp33c.tech.

Children

Lucerna is a document reader that collects no personal data from anyone, of any age.

Changes

If this ever changes, the change will appear here with the date it was made, and — if it concerns anything the app does with your data — in the app's release notes as well.

Last updated 8 August 2026. Questions: info@sp33c.tech.