Effective 1 September 2026. This replaces the version of 22 May 2025.
This policy explains what happens to personal data when you use the KnowDrugs apps for Android and iOS, and the knowdrugs.app website. The two are described separately, because they work differently.
Controller
Plant Product Design UG (haftungsbeschränkt)
Mahlower Str. 24, 12049 Berlin, Germany
Represented by Managing Director Philipp Kreicarek
Privacy contact: [email protected]
We apply the same data protection standards to everyone who uses KnowDrugs, wherever you live.
The short version
KnowDrugs is a harm-reduction app. People use it to look up things they may not want linked to their name, so the app is built to hold as little as possible about you.
- We never ask for location permission, and the app cannot read your device's location. Where we need a country or a city, we use your IP address or your device's time zone — or the city you pick yourself.
- No advertising identifier, no ad networks, no advertising profiles. We do not sell personal data, and we do not share it for advertising.
- Usage statistics can be switched off at any time, and they are not linked to your account.
- Experience reports are not linked to your account either. They are keyed to a random identifier that exists only on your device.
- We do record what you search for, so we can see what people are looking for that the app does not yet cover. It is not linked to your account.
- You can use most of the app without an account.
1Using the KnowDrugs apps
1.1Without an account
You can browse warnings, substances, safer-use information and counselling services without registering. Choosing to continue without an account still creates an anonymous account with our hosting provider so the app can read data and store your settings. It holds a random identifier and no details about you. You can delete it in the app at any time.
Legal basis: Art. 6(1)(b) GDPR — providing the service you asked for.
1.2Accounts
You can register with an email address and password, or with your Google or Apple account.
We store your email address, the sign-in method you used, your app language, and the times your account was created and last used. If you sign in with Google or Apple, we receive your email address from them and nothing else we keep; we never receive your password.
If you register with an email address and password, the password is handled by our authentication provider and stored only as a cryptographic hash. We never see or store your password.
Legal basis: Art. 6(1)(b) GDPR.
1.3Where you are
Several parts of the app depend on a country or a city — which warnings apply to you, which counselling and drug-checking services are near you.
The app never requests location permission and cannot read your device's location. Instead, in this order:
- The city you choose, if you set one. Stored on your device.
- An approximate location from your IP address, determined at our content delivery provider's network edge. The result is a city or country. We do not store your IP address.
- The country implied by your device's time zone, worked out on the device with no network request at all.
Where the time zone contradicts the network answer — typically roaming or a VPN — we reduce the result to a country rather than a city.
Anything we record alongside a location also records how it was obtained and how precise it is, so a location you told us is never mixed up with one we inferred.
Legal basis: Art. 6(1)(f) GDPR. Our legitimate interest is showing content that matches the country or city you are in. We use the least precise method that answers the question, and request no device permission.
1.4Usage statistics
To understand which parts of the app are used and where they fall short, we collect usage statistics through Google Analytics for Firebase.
You can switch this off at any time under Settings ▸ Privacy. Until you do, it is on.
What is collected: screens you open, features you use, and what you search for — together with your device type, operating system and app version. Your survey answers are not collected.
We record search terms because they are the only thing that tells us what someone looked for and did not find, which is how we decide what the app should cover next. Text that is plainly not a search — anything containing an email address or a phone number, or a passage long enough to be pasted prose — is replaced before it is sent, and never leaves your device.
These statistics are tied to a random identifier for this installation of the app. They are not linked to your account: we deliberately send no user identifier, so this data is not connected to your email address, your reports, or anything else you do in the app. Deleting your account resets that identifier.
Legal basis: Art. 6(1)(f) GDPR. Our legitimate interest is understanding how the app is used so we can improve it. You may object at any time under Art. 21 GDPR, which the switch in Privacy settings does immediately and without needing a reason.
1.5Crash reports and performance
We collect crash reports and performance measurements — the technical state of the app when something fails or runs slowly, plus your device model, operating system and app version. This is diagnostic data about the software. It contains no account details and is not used to build a picture of you.
Legal basis: Art. 6(1)(f) GDPR. Our legitimate interest is keeping the app stable, which requires diagnostic reports from the devices where faults occur.
1.6Push notifications
If you allow notifications, we can alert you to new drug warnings. Your device registers with Google's messaging service to receive them. The app does not read or store your device's notification token. You can turn notifications off in your device settings at any time.
Legal basis: Art. 6(1)(a) GDPR — your consent, given through the permission prompt.
1.7Experience reports
If you choose to submit an experience report, the app asks which substance you want to report on and then about the effects observed — unusual effects, after-effects, mood. Because answers of that kind can reveal information about health, we treat them as a special category of personal data.
We ask for your explicit consent before your first report, and you can refuse or withdraw at any time without losing the use of the app.
Reports are not linked to your account. Each one is keyed to a random identifier generated on your device, which we never store next to your account and which never appears in usage statistics. A report carries your answers, that identifier, and — only if you have picked a city yourself — that city. We use the reports to detect adulterated or unexpectedly strong substances and to publish aggregated harm-reduction information. Published results are aggregated.
You can erase all of your reports at any time under Settings ▸ Privacy.
Legal bases: Art. 9(2)(a) GDPR — your explicit consent, for the health information in the report. Art. 6(1)(a) GDPR for the processing itself.
1.8Image search and image donation
Image search compares a photo with our database and shows entries for similar-looking pills.
By default the photo stays on your device. The comparison runs on the device itself, the photo is not uploaded, and the feature works without a connection.
Image donation is a separate, optional setting. It is off unless you switch it on, and you can switch it off again at any time. While it is on, the photo you searched with is also sent to us so we can improve image search. In that case:
- Only the cropped area containing the pill is sent, not the whole photograph.
- All camera metadata is removed, including any location the camera recorded. The upload is rejected if that removal cannot be verified.
- What is sent carries the label, the colour, and your country and city — no account identifier and no device identifier.
- The image is kept indefinitely and used to improve image search.
A donated image cannot be withdrawn afterwards. Because nothing links it to you, it cannot be identified as yours — that is what keeps the donation unidentifying, and it is also why it is irreversible. Please only donate photos you are comfortable contributing permanently.
Legal basis: Art. 6(1)(a) GDPR — your consent, for the upload.
1.9In-app surveys
Occasionally we ask a short question inside the app. Answers are stored with your account so we do not ask twice, and to understand what people need. Survey answers are not sent to our analytics provider. From your answer to our product survey we derive one coarse label (for example "positive" or "neutral") for statistical purposes.
Legal basis: Art. 6(1)(f) GDPR — our legitimate interest in improving the app. Answering is always optional.
1.10Supporter subscriptions and unlocks
Purchases are made through the App Store or Google Play, which handle payment. We never receive your payment details. We use RevenueCat to check receipts and keep your purchase valid across devices; it receives your purchase status and an identifier linked to your account.
Legal basis: Art. 6(1)(b) GDPR.
1.11Newsletter
You can subscribe to occasional emails about drug-checking results and harm reduction.
We use double opt-in: asking in the app only records a request. We send one email, and the subscription starts only when you click the link in it. If you do not, nothing is sent to you.
Our email provider Brevo receives your email address, your app language, your account identifier, whether you are a supporter, the date your account was created, and — where you gave one — your product-survey answer.
You can unsubscribe in the app under Settings ▸ Privacy, or from any newsletter we send.
Legal basis: Art. 6(1)(a) GDPR — your consent, evidenced by the confirmation click.
1.12Consent records
Whenever you give or withdraw consent, we record what you decided, when, how you were asked, and which version of this policy applied. We are required to be able to demonstrate consent, and this is how we do it. They are kept as an append-only record.
Legal basis: Art. 7(1) GDPR together with Art. 6(1)(c) GDPR.
2The knowdrugs.app website
The website is separate from the apps and is where this policy is published.
Server logs. Our hosting provider records the usual technical data for each request — IP address, date and time, the page requested, browser and operating system. This is needed to serve the site and to detect attacks. Art. 6(1)(f) GDPR.
Cookies and similar technologies. Only strictly necessary cookies are set without your agreement. Everything else — analytics and marketing, managed through Google Tag Manager — runs only if you accept it in the cookie banner, which also lets you change or withdraw your choice at any time. Our consent banner is provided by CookiePro (OneTrust).
Legal bases: § 25(2) no. 2 TDDDG for strictly necessary cookies; § 25(1) TDDDG together with Art. 6(1)(a) GDPR for everything else.
Analytics. With your agreement we use Google Analytics with IP anonymisation, to see which pages are read. You can withdraw at any time through the cookie settings.
Social media. We maintain pages on Instagram and Facebook, operated by Meta Platforms Ireland Ltd. Meta processes visitor data for those pages under its own terms; for page statistics we are joint controllers with Meta under Art. 26 GDPR, and we receive only aggregated figures. Interacting with those pages is voluntary.
3Who receives your data
We do not sell personal data and do not share it for advertising. We pass it on only to the service providers below, who process it on our instructions, and where the law requires it.
| Recipient | What it does | Where |
|---|---|---|
| Google Ireland Ltd. / Google LLC (Firebase) | Accounts, database, notifications, usage statistics, crash and performance reports | EU and USA |
| RevenueCat, Inc. | Verifying purchases | USA |
| Brevo | Sending the newsletter | EU |
| Typesense | Search within the app | EU (Germany) |
| Cloudflare | Content delivery and approximate location | Processed at the network edge; provider US-based |
| Hetzner Online GmbH | Receiving experience reports and donated images | EU (Germany) |
| Apple, Google | Sign-in, if you use it; app distribution and payment | EU and USA |
| ipdata LLC | Approximate location — older app versions only, see section 1.3 | USA |
Transfers outside the EU. Some of these providers process data in the United States. Where they do, transfers are covered by the EU–US Data Privacy Framework and by the European Commission's Standard Contractual Clauses, together with additional safeguards. You can request a copy of these safeguards at [email protected].
We may also disclose data where we are legally required to, or to establish or defend legal claims.
4How long we keep things
| What | How long |
|---|---|
| Account data | Until you delete your account, then removed |
| Anonymous account | Until you delete it |
| Experience reports | Until you erase them; otherwise indefinitely, as research data |
| Donated images | Indefinitely — they carry no account or device identifier |
| Usage statistics | 14 months at our analytics provider |
| Crash and performance reports | 90 days |
| Newsletter contact | Until you unsubscribe or delete your account |
| Consent records | While the consent applies, then three years |
| Website server logs | A few months, then deleted or anonymised |
Why consent records outlive an account. Being able to prove that consent was given — or withdrawn — is what protects you if it is ever disputed, and we must be able to do it for as long as a claim could be brought. We keep the record for three years after the processing ends, which matches the German statutory limitation period, and we keep nothing else about you for that reason. This is permitted by Art. 17(3)(e) GDPR.
5Legal bases at a glance
| Purpose | Basis |
|---|---|
| Providing the app and your account | Art. 6(1)(b) |
| Location, at country or city level | Art. 6(1)(f) |
| Crash reports and performance | Art. 6(1)(f) |
| Improving the app through surveys | Art. 6(1)(f) |
| Usage statistics | Art. 6(1)(f) |
| Push notifications | Art. 6(1)(a) |
| Image donation | Art. 6(1)(a) |
| Newsletter | Art. 6(1)(a) |
| Experience reports (health information) | Art. 9(2)(a) with Art. 6(1)(a) |
| Proving consent | Art. 7(1) with Art. 6(1)(c) |
Where we rely on legitimate interests, we have weighed them against your interests in each case and described the result in the relevant section above. Where we rely on consent, you may withdraw it at any time; this does not affect processing that already happened.
6Your rights
You have the right to access your data (Art. 15), to have it corrected (Art. 16) or erased (Art. 17), to restrict processing (Art. 18), to data portability (Art. 20), and to object to processing based on legitimate interests (Art. 21) — including, at any time and without giving reasons, to any use for direct marketing.
Much of this you can do yourself in the app:
| What you want | Where |
|---|---|
| Turn usage statistics on or off | Settings ▸ Privacy |
| Turn image donation on or off | Settings ▸ Privacy |
| Subscribe or unsubscribe from the newsletter | Settings ▸ Privacy |
| Erase your experience reports | Settings ▸ Privacy |
| Delete your account and its data | Settings ▸ Account |
For anything else — including a copy of your data — write to [email protected]. We respond within the time limits the GDPR sets.
What deleting your account does not reach. Deleting your account removes your account and the data stored with it. It does not reach: experience reports, which are not linked to your account and have their own erasure control; donated images, which identify nobody; or your contact record at our email provider, which is unsubscribed rather than deleted. Usage statistics are unlinked from the installation at the same time. Ask us if you would like anything else removed.
Complaints. You can complain to a supervisory authority, in the EU state where you live, work, or where you think something went wrong. Ours is the Berliner Beauftragte für Datenschutz und Informationsfreiheit, Alt-Moabit 59–61, 10555 Berlin.
California residents. We do not sell or share personal information as those terms are defined by the CCPA, and we will not treat you differently for exercising a privacy right.
7Security
We use appropriate technical and organisational measures to protect personal data, including encryption in transit and at rest and access controls on production systems. Those measures are reviewed as the service changes.
8Age
KnowDrugs is not directed at children under 16. We do not knowingly collect data from them. If you believe a child has given us personal data, write to us and we will delete it.
9Automated decision-making
We do not make decisions about you by automated means, and we do not profile you within the meaning of Art. 22 GDPR.
10Changes
We update this policy when the app changes. The effective date at the top always tells you which version applies, and material changes are announced in the app.
11Contact
Questions about this policy, or about your data:
Plant Product Design UG (haftungsbeschränkt)
Mahlower Str. 24, 12049 Berlin, Germany
[email protected]
