Zifferl – Privacy
In short: Zifferl has no ads, no third-party analytics or tracking tools and no account. Your saved games stay on your phone. Only if you explicitly say yes does the app send anonymous play statistics to our own server.
What is stored on your phone
Your saved games, results, streak, records and settings are stored only on your phone, in the app’s own storage. To delete everything, clear the app’s data in the Android settings or uninstall the app.
Anonymous play statistics (only with your consent)
After your first finished game, Zifferl asks once whether you’d like to send anonymous play statistics. Without your yes, nothing is sent. You can turn statistics on or off any time in the settings; turning them off also deletes anything not yet sent.
What is sent if you agree:
- when a game ends: the mode, the target, points, cleared numbers, the number of chains and the longest chain, stars, hints used, whether it was a perfect or clean day, for the daily puzzle the weekday, and how many games you have finished so far (in ranges such as “6–20”);
- once a day when you open the app: how long you have had Zifferl (in ranges such as “4–7 days”), your current streak, and whether you opened it from the icon, the reminder or the widget;
- at most once a week your settings (theme, colours, tile style, font, sounds, vibration, big digits, reminder on or off);
- when you tap “Share”, that you shared (not what or with whom); whether the how-to was read to the end or skipped on first launch; that a widget was added;
- along with the app version, your phone’s language and the Android version.
What is not sent: no name, no email, no device, advertising or install ID, no contacts, no precise location, nothing from other apps.
How it works: the data travels encrypted (HTTPS) to our own statistics server running the open-source software Umami. As with any internet connection, the server sees your IP address. Umami does not store it: it only derives the rough country and region from it and, together with the app's user-agent string, a random value that changes every day. That lets us count visits within a day, but nobody can be recognised across days or as a person. The server keeps no access log.
Where and how long: the server is in a Contabo data centre in France; a backup copy is kept on a second server of ours at Contabo in Germany. Contabo processes the data only on our behalf. The statistics are deleted after 730 days. We don't pass them on to anyone and use them only to make Zifferl better.
Legal basis: your consent (Art. 6(1)(a) GDPR and § 165(3) of the Austrian Telecommunications Act 2021). You can withdraw it any time with the switch in the app's settings. As the data sent is not linked to a person, we cannot afterwards link it to you or delete it individually.
Android backup
If you have turned on backup in Android, Android may include your game data in the backup of your Google account, or move it to a new phone. Android does this for you; we have no access to that backup. You can turn it off in the Android settings.
Sharing
Only when you tap “Share” does Zifferl create a picture and a short text of your result and hand both to the app you choose. What happens after that is up to you and that app.
Reminder and widget
The daily reminder is a notification your phone shows by itself; it stays off until you turn it on. The widget shows today’s target and your streak from the data on your phone.
Google Play
If you install Zifferl from Google Play, Google processes data under Google's own privacy policy. Google gives us summarised statistics, such as the number of installs and crash reports from devices whose owners allowed sharing diagnostic data. We cannot identify individual people from them.
Children
Zifferl is not directed at children under 13 and does not knowingly collect data from them.
Who is responsible, and contact
dnp.studio – Florian Stangl
Handel-Mazzetti Straße 13
4690 Schwanenstadt, Austria
Email: apps@dnp.studio
You have the right of access, rectification, erasure, restriction of processing, data portability and objection. As the statistics are not linked to a person, we usually cannot link them to you; you can still contact us at any time. You can lodge a complaint with the Austrian Data Protection Authority (www.dsb.gv.at).
Changes
If what Zifferl does with data changes, we will update this page first and change the date at the top.