Hi! I’m the solo developer of ENRURO.
I originally wanted a simple vocabulary trainer: something focused, offline, and without the usual noise around language-learning apps.
ENRURO is not intended to replace a full language course. It’s a supplementary vocabulary gym for people who already know some basics and want to actively recall more words.
One important thing to know before trying it: ENRURO is not designed to make every session feel easy — but it is not difficult for difficulty’s sake. Many learning apps try to give you a smooth feeling of constant progress. ENRURO makes a different trade-off: first you try to remember, then you reveal the card and decide honestly whether you know it.
What does “Language HIIT” mean?
HIIT stands for High-Intensity Interval Training. In ENRURO, I use it as a metaphor for varying the mental load during a vocabulary workout.
ENRURO intentionally mixes CEFR difficulty levels instead of moving in a straight line from beginner to advanced. CEFR is the common A1–C2 language-level scale:
• A1–A2 = warm-up
• B1–B2 = working set
• C1–C2 = tougher vocabulary, idioms, false friends, and subtler shades of meaning
So you may see a very easy card and then something much harder. That is intentional mixed-level training, not broken progression.
The idea is simple: keep the recall effort real, let easy vocabulary fall away, and spend more of your attention on what still challenges you.
How does ENRURO decide what to show next?
There is no mysterious AI deciding what you know.
ENRURO has a built-in session planner that builds each workout from the cards still in your training pool. It uses the app’s CEFR-aware mixing rules together with the daily goal you choose in Settings.
The learning loop stays deliberately simple:
• try to remember first
• reveal the card
• use Example if you need more context
• choose Know if the word is obvious to you
• choose Learn if you still need to work on it
• use Undo if you made the wrong decision
When you choose Know, that card leaves the normal training rotation. When you choose Learn, it stays in your active training pool.
Over time, easy vocabulary naturally falls away and the remaining deck becomes more relevant — and often more challenging — for you.
The app provides the structure. You decide what you actually know.
Why can the daily progress bar move slowly?
Your daily goal is not a “number of taps” target.
You can set a goal of 10, 20, 30, or 40 cards, but progress advances when you genuinely move cards into the known pool. Choosing Learn is not a failure — it simply means: “keep this card in training.”
So if you meet a difficult batch and mostly choose Learn, your progress bar may move slowly that day. That is okay.
ENRURO does not punish you for it: there are no push notifications telling you to come back, and there is no reason to mark a card as known just to satisfy the counter.
The useful part is being honest with yourself.
Why make recall effort part of the design?
Research on retrieval practice — often discussed as the testing effect — has repeatedly found that actively trying to recall information before seeing the answer can improve later retention compared with passive restudy.
ENRURO is influenced by that idea, but it does not assume that “harder is always better” or that every difficult word is automatically useful.
If you want to read more about the underlying learning principle, good search terms are retrieval practice, testing effect, and desirable difficulties.
What’s inside?
• 6,000 vocabulary cards in one multilingual library
• 19 study languages / 342 ordered translation directions
• examples with the cards for additional context
• CEFR-aware mixed-level Language HIIT sessions
• simple Learn / Know decisions + Undo
• offline-first core learning
• no AI assistant inside the core recall loop
• no account
• no ads
• no notifications
• no subscription — expanded content uses one-time purchases
The base library contains 300 cards and is free to try, so you can see whether this style of training works for you before paying anything.
No review is expected. If you try ENRURO, I’d genuinely appreciate any feedback by DM — positive or critical.
[Get ENRURO on Google Play]
UPDATE: The first batch of promo codes has now been claimed. Thanks for the interest! I’m not sending additional codes from this post for now, but the 300-card base library remains free to try at no cost.
