Help & Support
Last updated: 7 October 2026
CapDex turns a photo of something in front of you into a flashcard in the language you are learning. This page covers how that works, what to do when it does not, and how to reach a person.
1. Getting started
- Sign in with Apple or Google. An account is required: your words live on the account, not on the phone, so they follow you to a new device.
- Choose your two languages — the one you speak and the one you are learning. Both are yours to pick, and either can be changed later in Settings.
- Point the camera at an object and capture it. CapDex lifts the subject off its background on the device, names it in both of your languages, and writes three example sentences.
- Check the name on the confirm screen, pick or create a collection, and save. The card is then in your journal and in the review schedule.
2. Capturing a word
The name is wrong
Type the correct word on the confirm screen. CapDex looks it up and replaces the card — translation, pronunciation and fresh example sentences included. A card you rename this way has no picture notes, so its Insight describes the word rather than the thing you photographed.
What makes a good capture
- one subject, filling most of the frame;
- even light, and a background the object stands clear of;
- if the subject is a dish, a plant or a sign rather than an object, that is fine — CapDex records what kind of thing it saw and explains it accordingly.
“CapDex couldn’t spot any word”
The photo was the problem: try another angle, move closer, or improve the light.
“The server is busy”
Not your photo. The model behind recognition was overloaded. Tap Retry — CapDex already retries on your behalf before showing you this, so a second attempt a moment later usually lands.
Nothing happens, or it fails straight away
Recognition needs a connection — the naming step runs on our server, not on the phone. Check that you are online, then retry. If the app says you are signed out, sign in again.
3. Languages
The interface is available in 15 languages and you can study 12 of them: English, Spanish, Japanese, Korean, French, Chinese, Vietnamese, German, Italian, Portuguese, Brazilian Portuguese and Russian. Cantonese, Thai and Indonesian are interface languages for now — you can read CapDex in them while studying any of the twelve.
Learning a language you already speak — English in English — is supported, and the card then shows one language on both halves.
Switching languages does not rewrite old cards. Each card remembers the pair it was made with, so your history still reads correctly. Practice decks only draw cards in the language you are studying today; your journal and collections show everything.
4. Reviewing
Cards come back on a spaced-repetition schedule: grade a card Again, Good or Easy and the next showing moves accordingly. A card counts as learned after three successful repetitions.
- Daily goal — set it in Settings. A day already finished keeps the goal that was in force on it; raising the goal later cannot reopen it.
- Streaks — capturing a word keeps the streak too, not only reviewing.
- Catch up — finishing an earlier day’s goal records against that day. On a day you never reviewed at all, it counts for today instead.
- Browse — flipping through flashcards without grading changes nothing and is not recorded as practice.
Tapping a word in an example sentence
Example sentences are split into the units you tap. Tapping one explains what it means in that sentence — in a sentence about a fan, Japanese つけて is “turn on”, not “attach”. Japanese, Chinese, Cantonese and Korean sentences also carry a reading (romaji, pinyin, jyutping).
Hearing a word
Cards are read aloud with the voices installed on your phone. Voice, speed and pitch are per study language and set on this device — a new phone starts from its own defaults. If a language sounds wrong or silent, install its voice in iOS Settings → Accessibility → Spoken Content → Voices.
5. Collections
Every card belongs to at least one collection. CapDex suggests a collection you already have when one fits, or proposes a new one. Remove a card’s last collection and it drops into Unsorted rather than being left loose — a card is never in none.
6. Free captures and Pro
A free account can save a limited number of captures for the life of the account. The count lives on your account, so reinstalling the app does not reset it. Pro removes that limit.
Pro is an auto-renewing subscription sold through the App Store. Payment, renewal and cancellation are handled by Apple — manage or cancel it in iOS Settings → your name → Subscriptions, or from the Profile screen in the app. Deleting the app does not cancel a subscription.
Restoring a purchase: sign in with the same Apple Account that bought it and use Restore Purchases on the paywall. If an active subscription still does not unlock, write to us with the Apple Account email used for the purchase.
7. Your account and your data
- Sync — words, collections, pictures and review history live on your account and appear on any device you sign in to.
- Deleting a word removes it and its picture, and the grades it was given.
- Deleting your account, from the Profile screen, is final: you are signed out at once and cannot sign back in to that account. It needs a connection — an offline attempt would report a success it has not achieved. Closing the account is not the same as erasing what is in it; to have the words, pictures and history erased too, write to us.
- Signing in to a deleted account is refused, with “Your account was deleted. Try another account.”
What we store and why is set out in the Privacy Policy. To have an account deleted when you cannot reach the app, write to support@capdex.app.
8. Requirements
iPhone running iOS 18 or later, a camera, and a connection for naming words and syncing. Cards you already have can be reviewed offline; capturing a new one cannot.
9. Contact
Bugs, feature requests and anything this page does not answer: support@capdex.app. Sending the mail from the app’s support row attaches a short diagnostics block, which makes an answer much faster.