1Chinese Privacy Policy

Last updated: October 8, 2026 · 1Chinese for iPhone

This policy covers 1Chinese, the HSK Chinese tutor for iPhone, including its optional AI and purchase services. It is complete on its own; the 1Buck Apps Privacy Policy describes the principles shared by every app of the line.

1. Who is responsible for 1Chinese data

1Chinese is developed by Anton Trantin, an independent developer publishing as Antosha Apps under the 1Buck Apps brand ("we", "us"). We are responsible for the processing described here. Contact us about privacy or support at [email protected].

2. 1Chinese learning data on your iPhone

Your goal and study settings, placement results, words and their review schedule, answers, mistakes, lesson and exam results, and practice drills made from your tutor conversations are stored only on your iPhone. Tutor conversations themselves are not saved after you close them; only the practice drills you choose to save from them are kept. The counters for the free version's daily limits are also kept on the device. We do not upload your learning history to our server, and 1Chinese does not use iCloud sync.

Like other app data, this data can be part of your own iPhone backup (iCloud or computer) according to your iOS settings; we have no access to those backups. Deleting the app removes its learning data from the device. The random install id and session key of your AI credit wallet are kept in the iOS Keychain on this iPhone only; iOS may keep them after the app is deleted. There is no 1Chinese account, so we cannot restore your learning history.

The Chinese audio built into the app (words, sentences, listening tasks) was produced in advance by us with ElevenLabs text-to-speech and plays from the device. Listening to it sends nothing to anyone.

3. What 1Chinese AI features send

AI features are optional. They require internet access, the 1Chinese Gold subscription and AI credits. Every AI request goes from the app to our server, and our server forwards it to the provider using our own access keys; the app contains no provider keys and never contacts a provider directly.

• AI tutor conversations, conversation review and written answer checks (OpenAI): we send what you typed or said (as text), the conversation so far (up to the last 30 turns, each marked as typed, spoken or a tapped hint), the topic, the vocabulary allowed at your level, your HSK level, the app language and the task instructions. For a written answer check we send the task, the required words, your HSK level, the app language and your answer. The reply contains the tutor's turn, corrections or feedback.
• Speech recognition (ElevenLabs): when you record a spoken reply to the tutor or a "Repeat after me" sentence, the recording (up to 90 seconds) is sent for transcription into Chinese text. The app keeps the recording only in temporary storage on your iPhone and deletes it after a successful transcription; if the request fails or you cancel it, the file stays in the app's temporary folder until iOS clears it. In a conversation, the transcript then goes to OpenAI as part of the conversation.
• Spoken tutor replies (ElevenLabs): when a tutor reply is voiced (automatically after your spoken answer, or when you tap it to listen), its Chinese text is sent to ElevenLabs text-to-speech to create the audio. We use preset voices; your voice is never cloned.

These are recorded turns, not live calls. Please do not include sensitive personal details or information about other people in a message or recording.

We use AI content only to provide the feature you asked for. We do not sell it, use it for advertising or use it to train AI models. The providers process the data under their own API terms. We send text requests to OpenAI with response storage turned off (store: false). According to OpenAI's API data controls, data sent to the OpenAI API is not used to train its models unless the customer opts in, and abuse-monitoring logs are normally kept for up to 30 days, with longer retention possible for legal or safety reasons. Response storage being off does not remove all provider retention, including applicable prompt caching. See also OpenAI's privacy policy. ElevenLabs processes recordings and texts under its own terms; ElevenLabs' privacy policy describes how long it keeps data and that it may use data to improve its models, subject to its customers' data-use settings. Provider retention is governed by their terms, not by this policy.

4. What the 1Chinese server keeps

Our server works as a protective proxy. It does not log the content of your texts, recordings, transcripts or AI answers and does not save it in its database; the only copy is the encrypted retry cache below. To run AI credits without an account, it keeps technical records without content:

• Credit wallet and session: a one-way hash of the random install id the app creates (kept in the iOS Keychain on your iPhone), an encrypted session key, your credit balance and the dates of your plan period.
• Per AI request: the request id and the provider's own request id, a one-way hash of the request, the operation type (text, transcription or speech), the model, the provider, token, second or character counts, cost, credits charged, status and time.
• Retry cache: a completed AI result (the tutor's reply, the transcript of your recording or generated audio) is kept encrypted in memory (Redis) for up to 15 minutes, so that a retry after a dropped connection returns the same answer without charging you twice. Then it expires and is deleted from the live cache. An encrypted copy can remain in the server's periodic memory snapshot until that snapshot is overwritten.
• Logs: our application's error log records only error codes and technical event names, never content. Abuse limits use counters keyed by a hash of your IP address that expire within about an hour; hashing alone does not make them anonymous. Web server and network logs can contain your IP address, the time and the requested path, without the content of texts or recordings, and are kept for a limited time.

Voice recordings are processed only for the duration of the request and are not stored on our server. Each request also carries technical headers (app version, device model and system language) that the server does not store. Requests, including their content, pass through Cloudflare, our network provider, on the way to our server; see Cloudflare's privacy policy. These records are associated with your installation and credit wallet, not with a name or e-mail account you create with us. Install and purchase identifiers are pseudonymous technical records; they are not necessarily anonymous. We do not use them for tracking or advertising.

Deleting the app does not delete the server-side wallet and accounting records; they are kept as long as needed to operate credits, verify purchases, prevent abuse and handle disputes. Technical wallet and accounting records may also be present in server backups. Backup copies follow the backup system's rotation schedule, rather than the 15-minute AI-result expiry. The last backup copies can be retained longer if new backups stop. Deleting the app does not immediately remove records from backup copies.

5. 1Chinese purchases

Apple processes subscriptions and credit-pack payments; we never receive your payment details. See Apple's Privacy Policy. StoreKit checks your subscription on the device. To grant AI credits, the app sends each App Store transaction (a purchase, a renewal or a credit pack) once to our server as Apple's signed transaction. The server verifies Apple's signature and keeps a one-way hash of the transaction id with your credit wallet, together with the product, plan and period dates, so the same purchase cannot be credited twice. The signed transaction itself is not stored. This record is linked to your installation's credit wallet. We do not use it for tracking or advertising.

6. 1Chinese problem reports and support e-mails

The "Report a problem" flag opens your own mail app with a draft e-mail to [email protected]. The draft contains the id of the task, word or sentence, its type and text, the ids of its audio clips, your answer and the app's answer, the app version and build, and the app language. You can edit it, and nothing is sent unless you send the e-mail yourself.

If you e-mail us, we receive your e-mail address, the message and anything you attach, and use them only to answer you and fix the problem. We do not add you to marketing lists.

7. 1Chinese permissions

• Microphone: asked only when you first record a spoken answer. You can refuse it or turn it off in iOS Settings; everything else keeps working.
• Internet: needed for AI features, the credit wallet and App Store purchases or restoration. Lessons, practice, exams and bundled audio work offline.

1Chinese does not access your contacts, photos, camera or location, does not send notifications and does not use the advertising identifier.

8. Data categories used by 1Chinese

The processing described above includes audio data (recordings sent for transcription), user content (text sent to the AI tutor and answer checks), purchase records (App Store transactions verified to grant AI credits) and installation identifiers (the random id used by the credit wallet). We use these for the requested features, purchases and service security. We do not use them for advertising or cross-app tracking. The App Store privacy information summarizes data practices; this policy explains the full flow and retention.

9. Children and 1Chinese

1Chinese is not directed to children under 13 and we do not knowingly collect personal data from children.

10. 1Chinese processing purposes and transfers

Where European data-protection law applies, we process the data needed to provide the AI features and purchases you request to perform our agreement with you. Security, abuse prevention and answering support requests rely on our legitimate interest in a reliable service. We may keep records to meet legal obligations.

AI, payment and network providers may process data in countries other than yours, including outside the European Economic Area. Their terms and privacy notices describe processing locations and transfer safeguards.

11. Your choices and rights in 1Chinese

You can learn without AI, avoid personal details in messages and recordings, revoke microphone access in iOS Settings and delete the app to remove its local data. Deleting the app does not cancel a subscription; manage it in your Apple Account settings.

Depending on where you live, you may have the right to access, correct, delete, restrict or receive a copy of personal data we hold, and to object to processing based on legitimate interests. You can also complain to your data-protection authority. Write to [email protected]. Because there is no account, we may need details such as a purchase date to find records linked to your installation. Data already processed by an AI provider is covered by that provider's own privacy notice and request process.

12. 1Chinese policy changes and contact

If our practices change, we will update this page and its date; material changes will also be noted in the app's release notes. Questions? Write to [email protected].