Privacy Policy

BlowWater · Last updated 8 August 2026

BlowWater is an app for practising a language by chatting with other people who are learning too. This page explains what the app collects, what it does with it, and who else sees it. BlowWater is operated by Cheung Pak Wai, and “we” and “us” mean us.

BlowWater is for people aged 18 and over.

What we collect

Your account. Your nickname and email address, and either a password or an identifier from Sign in with Apple or Google Sign-In. If you use a password we store only a hashed version of it, never the password itself.

Your profile. Your sex, age, a short bio, a profile photo, the language you speak and the language you are learning.

Where you are. Your approximate location and the name of your area, so the app can show you learners nearby. This is only sent while you give the app location permission, and you can withdraw it at any time in iOS Settings — matching will then be unable to find people near you.

Your conversations and learning. The messages you send and receive, stored both as you wrote them and as they were translated, along with reactions, replies, read state and timestamps. Also the words you bookmark and the message each one came from, and your quiz settings.

Your device and purchases. A notification token so we can send push notifications, a record of your in-app purchases and your remaining balance, and for each translation the AI model used, the number of tokens and what it cost.

Safety. The accounts you block, and any reports you send us.

When something goes wrong. If a request in the app fails, it sends us a short report so we can find the fault: the app and iOS versions, your device model (“iPhone 14 Pro”, not an identifier for your particular phone), which part of our API failed, the status code it returned, a brief error code, and your account id if you are signed in. It does not include the contents of your messages, your photos, your name or email, your location, or any advertising identifier.

What we do with it

• Show you people nearby who are learning the language you are learning.
• Translate your messages so you can hold a conversation before you are fluent.
• Send you notifications about matches and messages.
• Keep your word list and build your daily quizzes from it.
• Process purchases and track your balance.
• Act on blocks and reports.

Who else sees it

• Apple — Sign in with Apple, push notifications, and verifying in-app purchase receipts.
• Google — Google Sign-In, push notifications on Android, and verifying Google Play purchases.
• Amazon Web Services — profile photos are stored on S3 and delivered through CloudFront using links that expire.

We do not sell your personal information, and we do not share it with anyone for advertising.

What stays on your phone

• The profile picture check. When the app checks that your profile picture contains a face, that runs entirely on your device using Apple’s Vision framework. The photo is not sent anywhere to be analysed — only the yes-or-no answer reaches us.
• Dictionary lookups. The dictionary and the furigana readings are built into the app. Tapping a word to see what it means does not contact any server.
• Pronunciation practice. This uses your microphone. Recognition runs on your device when iOS has the speech model for that language installed; if it does not, iOS sends the audio to Apple to recognise it. Either way the recording never reaches us — we receive only whether what you said matched.

What we don’t do

BlowWater contains no analytics SDK, no advertising SDK and no third-party trackers. The only outside components in the app are the ones for signing in and for reading Japanese text. We do not profile you for advertising, and we do not sell data to anyone.

That includes the error reports described above: they go only to our own servers, never to a third-party crash-reporting or analytics service, and they are read to fix faults rather than to measure you.

Keeping and deleting your data

You can delete your account from inside the app, under your profile. When you do, we remove your email address, name, password, Apple and Google sign-in identifiers, profile photo, bio and location, delete the photo itself from storage, and sign you out everywhere. Your conversations disappear from the other person’s chat list and can no longer be opened.

To be straightforward about the part that is not erased: the messages themselves, and the words saved from them, remain in our database rather than being deleted. A conversation belongs to two people, and we do not remove one person’s side of it from the other’s account. If you want your messages removed as well, email us and we will do it.

Error reports are deleted automatically after 30 days, whether or not they were attached to an account. We keep everything else for as long as your account exists.

Your choices

• Location and microphone permissions can be turned off at any time in iOS Settings.
• Push notifications can be turned off in iOS Settings or in the app.
• You can change or clear your profile details in the app.
• You can ask us for a copy of your data, or ask us to correct or delete it, by emailing the address below.

Security

Passwords are stored only as bcrypt hashes. Traffic between the app and our servers is encrypted in transit. Profile photos are served through links that expire, so a copied URL does not stay valid.

No service can promise perfect security, and we would rather say so than imply otherwise.

Children

BlowWater is not intended for anyone under 18, and we do not knowingly collect personal information from children. If you believe a child has created an account, email us and we will remove it.

Changes to this policy

If we change how the app handles your information, we will update this page and change the date at the top. Significant changes will also be announced in the app.

Contact

Questions about privacy, or requests about your data: hello@blowwater.app.