This policy describes, in plain terms, what Daily Brain Challenge collects and why, for anyone using the app outside Korea. If you're using the app in Korea, the Korean-language policy applies to you instead — the app is developed and operated from Korea, and that version is written to Korea's data protection law.
We take your privacy seriously and want you to understand exactly what this app does with your information before you use it.
| Required | Display name (nickname), avatar colour, account identifier (a randomly generated UUID) |
|---|---|
| Service usage records | Dates played, scores per activity, list of completed activities, consecutive-day streak, XP and level, and the device time zone at the moment a record is written |
| Sensitive information | Measurements of change in performance across cognitive domains
(memory, language, temporal orientation, and others) Stroke measurements recorded in the “Handwriting” and “Signature” activities (writing speed, line steadiness, stroke count), together with a reduced-size image of what was written These items are stored only on the user's device and are never transmitted to a server. |
| Optional | Email address and password (only if you choose to make your account recoverable beyond this device) |
| Voice (optional feature) | Speech captured while you hold the microphone button during the
“Word Fluency” activity. It may be sent to Apple's speech recognition
service to be converted into text. No recording and no recognised word is stored on the device or on a server; when the activity ends, only the number of words you said is kept as a score. |
| Crash reports | Technical information kept when the app stops unexpectedly: the error
message, the screen it stopped on, the app version, and whether it was
running on iOS or the web No game content, handwriting, or words you typed or said is included. |
The app does not collect legal names, government ID numbers, phone numbers, home addresses, or payment information. It uses no advertising identifiers and no third-party analytics tools. It does not access location, contacts, or photos. The microphone is used only while you press the microphone button during the “Word Fluency” activity, and is never switched on at any other time.
You can use the app without an email address. The app starts with an anonymous account and no sign-up step. An email address and password are collected only if you register them yourself, so that your records can be recovered if you change devices or reinstall the app.
Your voice is not kept. When you press the microphone button in the “Word Fluency” activity, your speech may be sent to Apple's speech recognition service to be turned into text. The app keeps no recording, and does not store or transmit the recognised words either. When the activity ends, only how many words you said is recorded as a score. You can decline microphone access and still do the same activity by typing the words in.
The cognitive-change measurements the app produces may constitute sensitive information, as information concerning health. The app therefore asks for separate, explicit consent for the collection and use of that information, distinct from consent for other personal information; you will see this on the consent screen when you first run the app.
Handwriting and signature records are treated as the same kind of sensitive information. The “Handwriting” and “Signature” activities store stroke measurements — writing speed, line steadiness, stroke count — and a reduced-size image of what was written, kept separately for each profile on the device. They exist so that a person can look back and compare how their writing has changed over time. The app does not judge what any change means. It is not information that diagnoses or predicts a health condition.
You can turn this record off at any time in Settings, and delete what has already been stored. Turning on the setting that automatically removes records older than 30 days deletes the measurements and the images together. Both activities remain fully playable with the record switched off.
This data is computed on your device and stored only on your device. It is not transmitted to any server, and no other user — including members of your family circle — can view it. The cognitive-change records the app displays are generated directly from the values held on that device.
You may decline consent, in which case cognitive-change tracking is not provided. Consent may be withdrawn at any time by deleting your account within the app; deleting your account also erases the cognitive-change measurements stored on the device.
The app does not use collected information for advertising, marketing, profiling, or automated decision-making, and does not sell it.
Information is retained until you delete your account, and is removed immediately upon a deletion request. You can delete it yourself at Settings > Delete account in the app. On deletion, your account and the activity records, progress, and circle memberships linked to it are removed from the database together and cannot be recovered.
The app does not sell or provide your personal information to outside parties. It is shared only to the extent you choose, as follows.
| Scores and streaks | Visible to members of the same circle. You join a circle only by
receiving an invitation link and accepting it yourself. Once you join a circle, your scores and streaks are shared automatically. There is no separate sharing setting; accepting the invitation is itself your consent to that sharing. Sharing stops immediately when you leave the circle. |
|---|---|
| Detailed activity records | By default, visible to no one. They can be read only by one specific member you have individually authorised, and that authorisation can be withdrawn at any time, taking effect immediately. |
The app uses a small number of outside service providers to operate, listed below with exactly what each one handles.
| Provider | Supabase, Inc. |
|---|---|
| What they do | Account authentication and database hosting |
| Where data is processed | United States (Amazon Web Services, us-west-1 region) |
| What is sent to them | The required items, service usage records,
and optional items listed in section 1 Sensitive information (cognitive-change measurements, and handwriting and signature records) is never sent to them. |
| How | Over encrypted connections (HTTPS), at the time the service is used |
| How long | Until you delete your account |
In addition, if you use the microphone in the “Word Fluency” activity, your speech is sent to Apple as set out below.
| Provider | Apple Inc. |
|---|---|
| What they do | Speech recognition (converting what you say into text) |
| Where data is processed | United States (Apple's speech recognition service) |
| What is sent to them | Speech captured through the microphone
during the “Word Fluency” activity Account information, activity records and sensitive information are never sent to them. |
| How | Streamed over an encrypted connection while you hold the microphone button |
| How long | The app retains no speech. Handling and retention of what is sent follows Apple's own privacy policy. |
You can decline both. If you don't grant microphone or speech recognition permission in your device settings, no speech is sent anywhere, and you can use the “Word Fluency” activity exactly as before by typing the words in.
The app is not directed at children under the age of 14 and does not knowingly collect their personal information. If we learn that a child's information has been collected without the consent of a legal guardian, we delete that information without delay.
Whatever privacy law applies where you live, we offer these choices to everyone, everywhere the app is used.
You can also make these requests through the contact details below. We aim to respond within 10 days.
This app is a training and activity-logging tool for health and wellness purposes. It is not a medical device. No score or record the app provides is intended to diagnose, treat, or prevent any disease, and the app does not diagnose or screen for cognitive decline or dementia. If you have concerns about your health, please consult a qualified medical professional.
| Privacy contact | Eun Ji Jung (정은지) |
|---|---|
| Contact email | askeunji@gmail.com |
| Support page | Support and enquiries |
We're a small, family-built app rather than a large company, and the fastest way to reach a real answer about your data is the email above. If your local privacy law gives you a right to escalate to a regulator, your own country's data protection authority is where to do that.
If this policy changes, we will give notice through the app or this page beginning 7 days before the effective date. Where there is a material change to your rights, we will give notice 30 days in advance.