No, the app does not decide that. Grzybiarz is an assistant: it shows the most likely species with calibrated confidence, the features to check and the toxic lookalikes. You make the final decision to pick and eat, at your own responsibility.

Yes. Fruit-body detection, species recognition and downloaded maps work fully offline on your phone. Only the mushroom conditions index, maps of countries without an offline package and uploads to your account need a network.

Recognition runs on your phone, where the model scores the photo without a network connection. A photo leaves the phone only when you decide to send it: when you mark a find as public and agree to show the photograph, when you turn on the training contribution, or when you send frames in the tester programme. Finds stay on your phone until you mark them as public. Trips including the route go to your account so the history does not disappear with the phone; only you can see them, and you can turn the upload off in settings. You can also export everything to GPX or to a trip backup file.

The app returns several of the most likely species with calibrated confidence and a checklist of morphological features. The result is a hint based on a probabilistic model and is not meant as a final verdict. You always see why the model is confident or why it is not.

The full feature set (camera, litter detection, and offline maps) runs on Android and iOS phones. The web version is for browsing the atlas and learning.

The atlas covers over 100 Central European species with descriptions, seasonality, habitat and diagnostic features, compiled from mycological literature.

The app helps you build knowledge and flags risks, but it does not replace experience or consulting an expert. If you have any doubt, have the mushroom checked by an expert.

Critical pairs (for example penny bun vs Satan’s bolete, or parasol vs death cap) are always shown next to the recognition result, with an anatomical feature comparison, so you can decide with the full context.

The season limits of every species come from the atlas. We calculate the shape of the season and its peak from foragers’ observations in Poland on iNaturalist and GBIF since 2014. For rarer species we also use observations from Czechia, Slovakia and Germany, and when there is too little data the calendar marks the range as an estimate. The curve shows when foragers report a species most often; it does not show how much of it grows.

The app does not point to places and does not predict a flush of a particular species. It shows whether the weather favours the mycelium. The score from 0 to 100 comes from the measurements of the nearest IMGW station: rain from 7 to 12 days ago has the highest weight, and the average temperature, frost and humidity count as well. The strip for the next five days shows the same score, calculated from the weather forecast. The weather stations are in Poland.

Once you mark a species with the bell in the calendar or on the species card, the phone notifies you when its season starts and two weeks before it ends. In the settings you can also turn on a Friday overview of the species at their peak and a notification about good conditions after rain. The phone schedules the notifications, and the list of watched species does not reach the server.

It is a field game built into the app: virtual specimens stand in real woodland and in larger city parks, true to season and habitat, and catching one means naming the species in a quiz. The game also has the Grzybdex, levels, badges, a mycelium that grows from kilometres walked, and flush windows after rain. Once the forest data is downloaded, the game works without signal, and the leaderboard is opt-in.

Game specimens exist only on the map; nothing is drawn on the forest floor or pointed out for picking. The quiz teaches species features, but never decide about collecting or eating a real mushroom based on the game; that is what the atlas and the toxic-lookalike comparison are for.

In Poland, Czechia and Slovakia you download an offline map package and play with no signal. In Germany, Austria and Greece the forest data for your area downloads automatically, and once downloaded it stays on the phone and keeps working offline; the map is streamed, so you do not have to download a whole country before a holiday. Outside those countries the game shows a message that there is no data yet instead of an empty map.

Your friends see the name and photo from your profile, and that is what a friends list is for. The person you send an invite to sees them as well, because you are the one reaching out. Someone who sends an invite to you sees neither your name nor your photo until you accept: until then they see only a four-character tag. On the leaderboard you also appear as a tag by default, and a separate switch in your profile adds your name there. Routes, coordinates and catch times never reach friends. If your profile has no name, nobody sees one.

Open Settings, Manage account and press Copy under the recovery code. It is copied together with the account ID, and you need both to get the account back. Keep it off the phone: in a password manager or an e-mail to yourself. We do not hold the code: the server stores only its fingerprint, so none of us can read it back for you. Trips, finds, XP and the Grzybdex are saved on the phone so they work with no signal, which also means they are lost together with the phone. The account receives trips with history enabled, published finds and ranking points.

In Settings, open Manage account and choose “Sign in to an account from another phone”. The same screen appears on first launch under “Already have an account?”. Enter the recovery code, four groups of four characters; it also contains digits, including 0 and 1. Leave the “Account identifier” field empty and fill it in only when the code alone does not find the account, which applies to accounts created before August 2026. If you have lost the code and have an e-mail address linked, choose “No code? Sign in by e-mail”. The recovery code is not single-use and keeps working after you sign in.

A recovery code, for example HQT3-FTHC-G7ET-HFM3, is the password to your account. The app generated it for you and only you know it, so do not send it to anyone, including us. An invite code, for example GRZY-K7DM-9TQF, comes from us, and you enter it in the Tester programme; it opens the testing programme but does not sign you into any account. If somebody asks you for “the code”, check which one they mean.

The app is free.

Grzybiarz is on Google Play (Android 8.0 or later) and on the App Store (iPhone with iOS 15.1 or later). The app is free.