Acropolis: Tessera Audio Guide · Shahen Grigoryan IE · Effective 13 October 2026
Tessera has no accounts and no sign-in. Below is everything the app does with data, in full.
The app asks for your location while you use it, so it can show where you are on the plan of the site, guide you between stops and offer the story of the object you are standing next to.
Your GPS coordinates never leave your phone. They are not sent to us, not stored on any server, and not shared with anyone. They are not used for advertising or tracking. The one thing to know about is the error report described under Crash reports below: if the app fails, the screen recording attached to that report can show the plan with your position on it.
Payment is handled entirely by Apple. We never see your name, your email or your card.
To know whether the guide has been purchased, the app uses RevenueCat, Inc. RevenueCat receives an anonymous identifier generated on your device and the purchase status that Apple reports. It is not linked to your identity. See the RevenueCat privacy policy.
Audio and photographs are downloaded from our server. Like any web server, it records the usual technical request data — IP address, time, and which file was requested — in short-lived logs kept by our hosting provider, Cloudflare. We do not build profiles from them and do not connect them to purchases.
Once the guide is downloaded, the app works with no network at all.
After a purchase the app may ask permission to show a reminder if the guide has not finished downloading. The reminder is created on your phone, works without a network, and involves no push service: nothing about it is sent to us or to anyone else.
When the app crashes or hits an error, it sends a report to Sentry (Functional Software, Inc.), an error-monitoring service, so that we can fix the fault. The report contains the app version, the device model and operating system version, the technical trace of the error, a short trail of what you did just before it (which screens you opened and which buttons you pressed), the anonymous purchase identifier described above, and a short screen recording of the moments before the error. The recording shows the app screen, which can include your position on the plan of the site. It is made only when an error happens, never during ordinary use.
It contains no name, no email and no payment details: the app never asks for them. Reports are stored in Sentry’s European region. See the Sentry privacy policy.
The app uses Google Analytics for Firebase to understand how it is used: how many people reach the introduction, start a route or finish a download, and where they give up. This tells us what to fix and what to write next.
Firebase receives an identifier generated for this installation, the device model, the operating system version, and an approximate location derived from the IP address of the request — the country or region, never a position on the map — together with the events listed below. It does not receive your name, your email or anything you typed.
Events also carry the random purchase identifier that RevenueCat assigns to this installation, the same one crash reports carry. It lets us see what happened before and after a purchase or a refund. It is not derived from you and does not contain your name, email or payment details.
The events are: choosing a language, playing the introduction, opening the purchase screen, completing a purchase, finishing a download, starting a route, and listening to a stop. No coordinates are ever sent — the identifier of a stop you listened to is not your location, and your position is never included.
See the Firebase privacy information and Google’s privacy policy. Deleting the app removes the installation identifier; a fresh install is counted as a new one and cannot be linked to the old.
No advertising. The advertising identifier (IDFA) is not collected: the app is built with the variant of the analytics library that has no access to it. No cross-app or cross-site tracking. No selling or sharing of personal data. No accounts, so there is nothing to sign in to.
The app is not directed at children and collects no data that could identify anyone.
Photographs come from Wikimedia Commons under Creative Commons licences (CC BY, CC BY-SA, CC0) and public-domain works. The author and licence are shown under each photograph inside the app.
Tessera is an independent app. It is not affiliated with, endorsed by or connected to the Hellenic Ministry of Culture, the Ephorate of Antiquities of Athens, the Acropolis Museum or the American School of Classical Studies at Athens, which administer and excavate these sites.
We hold no data that identifies you, so there is no account to access or close. Deleting the app removes everything it stored on your phone. If you want the analytics or crash reports of your installation removed, write to us with the date and the device model and we will delete them.
If this policy changes, the new version appears at this address with a new effective date.
Shahen Grigoryan IE, Armenia
tesseraguides@proton.me