Connect Your AI

Knowmad is a reading app for iPhone and iPad that helps you remember what you read and learn new words. You can use your own OpenAI or Google Gemini account for its AI features on any iPhone or iPad. This guide shows how to create an API key, add it to Knowmad and keep your spending under control.

Steps checked October 2026.

Do you need this? On devices that support Apple Intelligence, Knowmad's AI features already run on the device for free. A key is useful when your device doesn't support Apple Intelligence, or when Apple Intelligence doesn't support the language of your book.

Without any AI, you can still write flashcards yourself and translate words on the device.

What a key is used for

Explaining a word, with example sentences and synonyms
Translating a word
Suggesting a flashcard question from your answer
Making a flashcard answer concise, or turning it into key points

Knowmad contacts your provider only when you look up a word or ask for help with a flashcard. Nothing runs in the background. Knowmad adds no charge: you pay your provider directly for what you use, and a typical word lookup costs a fraction of a cent.

Both providers work only in some countries. Check OpenAI's list and Google's list before you pay for anything.

Create a Google Gemini key

You don't need to pay to start. Both Gemini models in Knowmad work on Google's free tier, which has daily limits.

Open Google AI Studio and sign in with your Google account (you must be 18 or older).
Accept the terms. If this is your first visit, AI Studio has already made a key for you; if not, tap Create API key.
Copy the key.
If Knowmad later says Gemini isn't available in your region, turn on billing for the key's Google Cloud project. In some regions the Gemini API works only with billing turned on.

Spending: in Google Cloud Billing you can create a budget with alerts. Google's budgets send you a notice when spending reaches the amount you set; they don't stop requests.

Create an OpenAI key

Open the OpenAI API keys page and sign in. This is the OpenAI developer platform; a ChatGPT subscription doesn't include API use.
Add a payment method or prepaid credit in the platform's billing settings.
Tap Create new secret key, give it a name such as "Knowmad" and copy the key. OpenAI shows the key only once.

Spending: in the platform's limits settings you can set a monthly budget for the project the key belongs to.

Add the key to Knowmad

Open Settings → Connect Your AI and choose Gemini or OpenAI.
Read the note about which text is sent, and turn on the consent switch.
Paste your key.
Keep the suggested model (GPT-6 Luna or Gemini 3.5 Flash-Lite). It costs the least and works well for word lookups. Reference prices, in US dollars per million tokens, are listed under Offered Models.
Tap Verify. Knowmad sends one short test request to check that the key and model work.
Tap the checkmark in the top-right corner.

The provider and model you save are used for new books. To change what answers in a particular book, use the AI button in the bottom-left corner of the word or flashcard screen. Every AI result shows where it came from: Apple Intelligence, your provider and model, or Translation.

Good habits

Create a new key just for Knowmad. Your provider's dashboard then shows exactly what Knowmad uses, and you can delete the key without affecting other apps.
Set a spending limit or alert with your provider before you start.
Keep your key private. Knowmad never shows a saved key again.

What is sent, and where your key is kept

For a word: the word, its part of speech and the sentence it appears in, or the text you selected.
For example sentences: the word and up to 20 words from your saved words in that language, so the examples can use words you know.
For a flashcard: the text of the answer you're working on.

Requests go straight from your device to your provider. They don't pass through any Knowmad server, and we never see your key, your text or the results. Your key is stored in your device's Keychain and, if you use iCloud Keychain, synced to your other devices. On each new device, Knowmad asks for your consent again before sending anything. Details are in the Privacy Policy.

Remove a key

Open Settings → Connect Your AI, choose the provider and tap Remove Key…, then Remove From All Devices. The key is removed from all your devices. To stop the key from working anywhere, also delete it on your provider's website.

Problems

Knowmad says there is a problem with your provider setup

The key may be mistyped, deleted or out of credit, or your account may not have access to the chosen model. Check the key and billing on your provider's website, then open Settings → Connect Your AI, choose a model and tap Verify again.

Knowmad says you've reached your provider's usage limit

Your provider account has reached a rate limit or, on Gemini's free tier, its daily limit. Nothing is wrong with your setup. Try again later, or raise the limit in your provider's dashboard.

Knowmad says the provider is not available in your region

The provider doesn't offer API access where you are. For Gemini, turning on billing for the key's project often solves this.

A request failed while I was reading

Knowmad shows a message without closing the screen. Tap Retry, or, if your device supports Apple Intelligence for the book's language, use Apple Intelligence for the rest of that lookup. Knowmad never retries a paid request by itself.

Still stuck? Contact support. New to Knowmad? Get Knowmad on the App Store.