Tetr for iPad and iPhone, and the Tetr AI service · Version 4 · September 23, 2026 · Terms of service
The short version. Tetr has no accounts, no analytics, no advertising, and no tracking. Your notes are files in your own storage and we never see them. The app comes with Tetr AI, our hosted assistant, set up as the default model. For that it connects to our servers when it starts, to keep a wallet of turns for your device, and when you ask, to pass your selection to an AI model. We keep the wallet, a ledger of turns, and one usage record per request. We never keep the content of your asks. You can switch Tetr AI off and use your own key or Apple's on-device model instead, and then nothing reaches us at all.
RESONATOR, LLC, Yerevan, Armenia, is the controller for everything described here.
Privacy questions: contact@resonator.am · Support: support@resonator.am
| Where | What | How long |
|---|---|---|
| Your storage | Your notes and everything derived from them, including AI answers and the record of each conversation. | Until you delete them. |
| Your device | Settings, configured AI models, API keys, your wallet key, and a short diagnostic log of what the assistant link did. | Until you delete the app or the Keychain items. |
| The provider you chose | Your selection and the note's transcript, when you ask. | Under that provider's policy. |
| Our servers (Tetr AI) | Wallet identity and code, balance, ledger of turns, one usage record per request without content, which app version your device runs. | As long as the wallet exists; deleted on request. |
| Anthropic | Your asks through Tetr AI, forwarded by our servers. | Under Anthropic's commercial API terms. |
| Apple and Ameriabank | Payment details when you buy turns. We receive neither. | Under their policies. |
Notes are stored only as files in the location you choose: a folder in your own iCloud Drive, Tetr's own folder in your iCloud Drive, or local storage on your device. A note is a PNG image, a Markdown transcript, an RDF sidecar, and, if you have used the AI features, an agent/ folder with each conversation turn: the cropped selection, the request, and the rendered answer. All of it is yours, readable without Tetr, and deletable with the Files app. If your notes are in iCloud Drive they sync through your Apple account under Apple's terms; we never see, receive, or store them.
Handwriting recognition runs on your device with Apple's frameworks. Nothing is uploaded for it.
Library/Logs/tetr-assistant.log, at most 32 KB): which requests were made, whether they succeeded, balances, and error text. It never contains note content or keys, and it leaves the device only if you send it to us yourself.Deleting the app removes the settings and the log. Keychain items can outlive the app; the wallet key is kept on purpose so you do not lose turns by reinstalling.
Tetr AI is the hosted assistant we run. It is the default model in every new install. You can pick another provider or remove it under AI Providers; with Tetr AI removed, the app makes none of the connections in this section.
The app opens a connection to our service and sends the public half of your wallet key, the app's name and version, and the first eight characters of your device's network identity. With that it creates your wallet on first contact and grants the free starter turns, reads your balance, fetches the list of available models, and finishes any purchase that was not credited yet. Beta builds also send Apple's signed statement about the install (the "app transaction", which carries an Apple-assigned id for the install, the bundle id, version, and original purchase date) once per build; it was used for a free beta grant that has since ended, and we keep no record of it. No note content is sent at start-up.
When you select part of a note and tap Ask, or tap Quick ask, the app sends:
If you configure your own key, the request goes directly from your device to the provider you chose: Anthropic, OpenAI, OpenRouter, Google, Groq, Mistral, DeepSeek, xAI, Together, Fireworks, Cerebras, Perplexity, or a server you run yourself such as Ollama or LM Studio. That provider's own terms and privacy policy apply. We never see the key, the request, or the answer. If you choose Apple Intelligence, the request is answered by Apple's on-device model and nothing leaves your device.
The microphone button dictates an instruction for the AI. Speech is recognised on your device with Apple's on-device recogniser; the button is hidden where that is unavailable. No audio is recorded or sent anywhere. Only the recognised text travels with your request.
Tetr AI is paid in turns. Turns live in a wallet on our billing server in Frankfurt, Germany. The wallet is keyed by your device's wallet key, so it is not tied to your name, email, address, or Apple ID. It is a Resonator wallet: another Resonator app on the same device would share the same wallet and its starter turns. For each wallet we keep:
Support staff can read a wallet's balance and ledger by its code, and can move or grant turns, for example after you change devices. Every such adjustment is written to the ledger and to a support log.
The billing server writes an hourly backup and keeps the last two days of them; a nightly copy goes to an administrative server in Germany and is kept for 30 days. Records therefore survive for up to 30 days after deletion.
Packs of turns are in-app purchases handled by Apple under Apple's terms and privacy policy. Apple takes the payment and knows your Apple ID; we do not. After a purchase the app sends our billing server the transaction receipt signed by Apple. The server checks Apple's signature, that the receipt belongs to Tetr and to the pack you bought, and that it has not been refunded, then credits your wallet. From the receipt we keep only the transaction id, the original transaction id, the product, the quantity, and whether it was a sandbox or production purchase, as the reference for that ledger entry. Refunds are requested from Apple. Apple then notifies our billing server with the transaction id, and the pack's turns are taken back from the wallet.
You can also add turns from a browser at billing.resonator.am by typing your wallet code and paying in Armenian drams with a bank card. The card page is hosted by Ameriabank; you enter your card details there, under the bank's own privacy policy, and they never reach us. Our server registers the order with the bank (an order number, the amount, and your wallet code) and afterwards asks the bank whether it was paid. From the bank's answer we keep the order number, status, amount and currency, the approval code and bank reference numbers, and the terminal id: enough to reconcile with the bank, nothing about you. The top-up site keeps an ordinary web-server access log (IP address, time, browser, page), rotated and discarded after a few weeks.
The 1.2 beta is distributed through Apple's TestFlight. Apple handles enrolment under its own terms and shows us what TestFlight shows every developer: the testers on the build, install status, and any feedback or crash reports you choose to send from TestFlight. Purchases made in a beta build are sandbox purchases: Apple never charges you, and our billing server credits them like real ones up to 500 turns per wallet.
tetr.md is static pages served from Amsterdam, the Netherlands: no analytics, no cookies, no forms, and no access logs.
Tetr collects no personal data from anyone, including children. Purchases require an Apple ID and go through Apple's own parental controls.
Under the GDPR and similar laws you can ask what we hold about you, have it corrected or deleted, and complain to a supervisory authority. Since there is no account, what we can hold is the wallet, its ledger, and the usage records for a wallet identity. Write to the address above with your wallet code, which you can read in the app under AI Providers. We delete the wallet and its records on request; deleting a wallet forfeits any remaining turns, and ledger entries tied to purchases may be kept where accounting law requires it. Backups expire 30 days later.
If this policy changes, the updated version is posted at this address with a new date. Version 1 (August 27, 2026) covered Tetr 1.0, which had no AI features and no server side. Version 2 (September 17) described the wallet and a beta mailing list that was never opened. Version 3 (September 23) described Tetr AI before it became the default model.
RESONATOR, LLC
contact@resonator.am