Studiary: AI English Diary

An English diary trains more than your writing.
Vocabulary, grammar, structure and expression — all of it, in one habit.

Studiary is an English diary app built on three steps: write, get corrected, review. Write about your day in English, and your English gets a little better every day.

■ Who it is for
・Anyone building a habit of writing in English
・Learners strengthening their composition and writing
・Anyone preparing for the writing section of IELTS, TOEFL or Eiken
・Self-studiers who want feedback without a tutor

■ Three simple steps
1. Write — about your day, with a prompt or by voice
2. Get corrected — the AI reviews the whole entry and explains every change
3. Review — spaced repetition brings each phrase back before you forget it

■ Features

◎ AI corrections, right after you write
Not just grammar — vocabulary, phrasing and naturalness too. Every change is shown with a strikethrough; tap it to read why it was changed.

◎ See your level on the CEFR scale
Every entry is graded on the international CEFR scale (A1-C2): an overall level plus separate levels for range, coherence and accuracy, so you can see where your weak spot is.

◎ Today's takeaways, and a polished version
Each correction surfaces two kinds of phrases worth keeping: level-up phrases that lift your own wording into a more natural form, and recommended collocations you have not used yet. Either becomes a review card in one tap. You can also read your whole entry rewritten a level higher — same content, better English.

◎ Nothing to say? Nicky asks. Stuck? Ask Nicky.
On days when nothing comes to mind, your AI coach Nicky asks you a question — answer it and the entry has already started. Can't find a word mid-sentence, or unsure the phrasing works? Ask while you write, and you get hints, alternatives, and questions about what to write next.

◎ But Nicky will not write it for you
Studiary is not an app that writes your diary. It will not draft your entry or translate long passages, even if you ask. It helps you past the point where you are stuck, and no further. Finishing it in your own words is what makes it stick.

◎ Remember what you learned
Phrases from your corrections are scheduled by FSRS, a spaced repetition algorithm, and come back at the right moment — phrases Japanese to English, words English to Japanese. A mastery percentage shows how well each has settled in.

◎ Voice, dictionary and audio
Write by speaking with English voice input. Select any English text to look it up in the built-in dictionary — no connection needed, and inflected forms resolve to their base form. Bookmark a word to turn it into a review card. Tap the speaker to hear any sentence read aloud.

◎ A calendar, a streak, and your past self
Days you write get marked, and your streak becomes a badge. On This Day digs up what you wrote on this date a year ago — the clearest proof that you improved. Full-text search finds any phrase you have used, and you can share a card with your streak and total word count.

◎ Nicky remembers you
Beyond the goals you set at the start, Nicky picks up your strengths, weak spots and preferences from your entries and feeds them into your corrections and questions. It also reacts to what you actually wrote, not only to your English — a correction that starts with "sounds like a rough day" is one you come back to tomorrow.

■ Built to be kept up
・Light and dark themes; interface in English or Japanese
・Your entries are stored on your device

■ About correction limits
One AI correction per day is included. To have another entry corrected the same day, watch a short video ad. Writing, re-reading, reviewing and looking up words are never limited.

■ Support
Send feedback and bug reports from the app's settings screen.

Start your English diary today.
A few minutes a day is what changes your English a year from now.