A German app whose AI knows which words you have learned and adapts
Last updated 2 June 2026
KLUG is a German learning app whose conversation partner reads your own progress before it speaks. When a chat starts, the app loads the German words you have already practised, your level, your total learned-word count, and your accuracy, and hands them to the AI as a tool it can look up. The AI uses that to steer toward words you know and to hold the conversation at your real A1 level instead of generic textbook phrasing. All of this runs on the device, with no third-party tracking and your data staying on your device.
What the AI actually sees before it talks to you
KLUG does not guess your level from a single placement quiz and then forget about it. Each time you open a conversation, the app reads your study history and packages it into a small lookup the AI can query while you chat. Concretely, it pulls together four things:
- Your learned words. The flashcards you have reviewed at least once, sorted so the words you have answered correctly most often come first.
- Your level. The current level the app has worked out from your progress, for example A1.
- How many words you have learned in total. A running count of the cards you have actually practised.
- Your accuracy. The share of your answers that have been correct, as a percentage.
The AI can ask for either the word list or the level summary at any point in the conversation. Its instructions tell it plainly to use this to match its language to the learner, so it leans on words you already know and keeps sentences within reach rather than reaching for vocabulary you have never seen.
Why this makes a real difference in practice
A generic chatbot writes German the way a textbook does. It has no idea whether you know the word for because yet, so it uses whatever is most natural for a fluent speaker. That is exactly the wall most A1 learners hit: the reply is grammatically perfect and completely over your head.
Because KLUG passes your real vocabulary in first, the conversation is built around the ground you have already covered. Early on, when your word list is short, the partner stays simple. As your learned-word count grows and your accuracy climbs, there is more for the AI to draw on, so the language can stretch a little further without leaving you behind. The companion fox, Fritzi, talks to you in German, and the conversation runs on the device. Your word list, your accuracy, and your chats are not sent off to a server to make this work. For a fuller look at the privacy side, see Private on-device AI, and for how the practice itself feels, see Practise German with AI.
How it compares
| Factor | KLUG | A generic AI chatbot |
|---|---|---|
| Knows which words you have learned | Yes, your reviewed flashcards are loaded before each chat | No, it starts from a blank slate every time |
| Matches your real level | Yes, your level and accuracy are passed in and the AI is told to adapt | No, it writes at a fluent speaker's level by default |
| Where the conversation runs | On the device | On a remote server |
| What happens to your data | Stays on your device, no third-party tracking | Typically sent to and processed in the cloud |
| Teaching language | German, at A1, with the fox companion Fritzi | Whatever you prompt, with no built-in level |
| Cost | Free to download and start, full access optional at 7.99 EUR per month or 59.99 EUR per year | Varies |
Frequently asked questions
How does KLUG know which German words I have already learned?
It reads the flashcards you have reviewed at least once and orders them by how reliably you have answered them, so your strongest words come first. That list, along with your level and accuracy, is handed to the AI before the conversation begins.
Does the conversation adapt as I improve, or is it fixed?
It adapts. Every time you start a chat, KLUG reloads your current learned words, your total count, and your accuracy, so the partner always works from your latest progress rather than a one-time setting.
Does my vocabulary or chat history get sent to a server?
No. The AI conversation runs on the device, and your data stays on your device. There is no third-party tracking or analytics.
What level does KLUG teach at?
KLUG teaches German in German at A1 level. The AI is told to use your learned words and level so it keeps the language within your reach, and the companion fox Fritzi guides you in German.
Is KLUG free?
KLUG is free to download and start. Full access is an optional subscription at 7.99 EUR per month or 59.99 EUR per year.
Which words does the AI prioritise when it talks to me?
The ones you have answered correctly most consistently come first, so the partner leans on vocabulary you have genuinely retained rather than words you only saw once.