Privacy Policy

Last updated 16 October 2026

This policy applies to all PuzzleMonster apps on iOS and Android: Fillomino, Hashi, Light Up, Masyu, Nonograms, NumRush, Nurikabe, Slitherlink, Star Battle, Suko, and Towers (the “apps”), including versions released before this date.

PuzzleMonster is operated by Nilsen Lab (“we,” “us”), which is the data controller for the information described here. You can reach us any time at lukas@nilsenlab.com.

The short version

No accounts and no third-party ads. The apps sometimes suggest our other PuzzleMonster games. Your puzzles, solve history and settings are saved on your device and are never uploaded. Android apps with the Share usage analytics setting keep analytics off unless you confirm you are 18 or older and choose to allow it. iOS versions without this setting send usage analytics to PostHog as described below. Android support opens your email app; iOS has an optional in-app feedback form. Optional tips are paid through Apple or Google, and the apps never receive your card details; a completed tip sends its amount and store transaction ID to PostHog only while analytics is enabled. The apps also contact Expo's update service when they start. Details below.

What stays on your device

Puzzle progress, your solve history and streaks, settings such as theme, and your supporter status and list of completed tips are saved on your device. We do not upload or back up this saved data, and it cannot be restored on another device. Uninstalling an app or clearing its data erases it.

Separately, starting or completing a puzzle sends the analytics event described below, which includes the difficulty and, on completion, the solve time. Those events are not a copy of your saved history and cannot restore it.

Usage analytics

On Android, analytics is off by default. Settings > Privacy > Share usage analytics explains the data sent to PostHog and asks for an adult confirmation and a separate Allow analytics choice. We store the consent version, date and adult confirmation on your device; we do not ask for a date of birth. Playing, tips and the badge do not depend on consent. Turning the switch off stops future analytics requests, including queued events. Turning it on does not replay earlier analytics events. If a pending tip finishes while analytics is enabled, its transaction details may be sent. iOS versions without this control retain the analytics behavior described below.

The apps use PostHog, hosted in the European Union, for product analytics. Each event includes:

• Which game you are using, the platform (iOS or Android) and the app version
• What happened: a puzzle was started at a given difficulty, a puzzle was completed and how long it took, and the app being opened, brought to the front or sent to the background
• How you use the apps' screens and prompts: opening and closing How to play, hints being offered, used or dismissed, picking a level, a review request being shown or accepted, another PuzzleMonster game being suggested or tapped, and the tip screen being viewed
• A random identifier that PostHog's software creates on your device and stores there, so events from the same install can be grouped, plus a temporary session identifier
• The time of the event, the device type, maker and model, the operating system and its version, the screen size, where available your language and time zone settings, and the analytics software version

The identifier is random and is not your name, email, phone number, Apple ID or Google account. It is not an advertising identifier. We do not turn on screen recording, session replay or automatic tap tracking.

All Android versions of the apps, and Suko 1.0.2 and later, ask PostHog not to estimate a location from your IP address. Earlier versions of Suko, and iOS versions of the other apps released before this option was added, did not turn it off, so PostHog may have derived an approximate (country or city level) location from the IP address of those requests. None of the apps collect precise location.

Feedback you send us

On Android, Contact support opens your email app after an adult confirmation. Nothing is sent automatically. Your email app sends your address and message to lukas@nilsenlab.com; the app does not insert an install identifier, activity history or purchase records. This support email is separate from PostHog analytics and does not require analytics consent.

iOS versions have an optional feedback form in Settings, and it can also appear after you finish a puzzle. When you send feedback, the message and the email address you typed (if any) are sent to PostHog as an event, together with the same random identifier and app details as the analytics above. That means feedback can be connected to the usage events from the same install. We use the email address only to reply to you.

Tips

The apps offer optional tips to support development. Each tip is a single in-app purchase, not a subscription, and does not unlock puzzles or gameplay features. On Android, the same home-screen supporter badge is also available free in Settings > Appearance > Show supporter badge. On iOS, a completed tip adds the badge. Payment is handled by Apple through the App Store on iOS and by Google through Google Play on Android, under their own terms and privacy policies (Apple, Google). The apps never see or store your card number or other full payment details.

When a tip completes while analytics is enabled, the app sends one event to PostHog with the product ID of the tip, the transaction ID from Apple or Google, the amount and currency, and where you opened the tip screen, together with the same random identifier and app details as the analytics above. We use it to count tips and to match them with store records. Apple and Google also give us records of purchases through their developer tools. Refunds are handled by Apple or Google.

Suggestions for our other games

After you finish a puzzle, an app may show a card suggesting another PuzzleMonster game, and each app has a More games list. These suggestions are for our own games only. The apps contain no third-party ad networks or advertising software. Seeing or tapping a suggestion sends the analytics event described above only while analytics is enabled.

Update checks

The apps use Expo's update service to fetch small fixes without a full App Store or Google Play update. When an app starts, it may contact that service and send the app name and version, your operating system and version, release channel information, a random installation token, and, if a previous launch failed, a short description of that error so we can fix it.

What we do not collect

• No accounts, passwords or contacts
• No precise location
• No photos or files
• No card numbers or other full payment details
• No advertising identifiers, and no data is sold or used for third-party advertising

How we use this information

We use analytics to see which puzzles and difficulties are played, find problems and decide what to build next. We use suggestion events to see which game suggestions players tap. We use tip events to count and reconcile tips. We use feedback to improve the apps and to answer you. We use update diagnostics to fix startup failures. We do not use any of it for third-party advertising or profiling, and we do not share it with data brokers.

We rely on your consent for optional Android analytics. We use support messages to answer your request, store records to manage tips, and update diagnostics to maintain the apps. For iOS versions without the Android privacy control, our stated basis for analytics is our legitimate interest in maintaining, improving and supporting the apps.

Children

The Android apps are intended for players aged 13 and over. Analytics is available only to people who confirm they are 18 or older and choose to allow it. Players under 18 can play with analytics off and can ask a parent or guardian to contact support. The adult confirmation is stored only on the device. iOS versions without these Android controls retain the analytics and optional feedback behavior described above. Tips use the purchase controls of the App Store or Google Play.

A parent or guardian can email lukas@nilsenlab.com with questions about a child's use of the apps, or to ask us to delete data from a child's install. As described under Your choices, we may need details such as the approximate time feedback was sent to find that install's events.

Where data is processed

Analytics, tip events and feedback are stored by PostHog on servers in the European Union. Update checks are handled by Expo (EAS Update). Tip payments are processed by Apple or Google. If you use the apps from outside the EU, analytics, tip and feedback data is transferred to and stored on PostHog's servers in the EU. EU hosting does not mean that all processing stays in the EU: PostHog and its service providers may process data in other countries, as described in PostHog's privacy policy and subprocessor list.

App stores

The apps are distributed by Apple through the App Store and by Google through Google Play. Apple and Google may collect information when you download an app or buy a tip, and if you turn on sharing of diagnostics or crash data at the operating-system level, they may collect it too. They do this under their own privacy policies, separately from the data described above.

How long we keep it

We keep analytics, tip and feedback events only as long as they are needed for the purposes above, after which they are deleted or kept only in aggregate form. Update diagnostics are stored by Expo as part of its update service under Expo's privacy policy; we do not set a separate retention period for them. Data stored on your device stays there until you delete it or uninstall the app.

Your choices

On Android, use Settings > Privacy > Share usage analytics to turn sharing off at any time. This stops future collection; it does not automatically delete events already received. The app shows an error if a privacy choice cannot be saved. Use Save analytics off before restarting if saving fails; you can use the switch to try allowing analytics again. You can use support email without enabling analytics.

You can contact us to ask what we hold, to correct it or to have it deleted. Analytics are keyed by a random identifier rather than your name, so to find your data we may need details such as the email address you used in the feedback form, the approximate time you sent it, or the order or transaction number from a tip receipt. To remove all locally stored data, uninstall the app. Email lukas@nilsenlab.com.

Changes

If this policy changes, we'll update the date at the top of this page.