REVU – spaced learning for people with real work to do

What REVU is

REVU is a spaced-learning companion for people who have to remember non-trivial things over months and years – exams, professional standards, languages, procedures, code, you name it.

Under the hood it uses proven scheduling algorithms (SM-2 / FSRS) to decide what you should see today and what can safely wait.

You don’t manage decks and intervals by hand; you just add cards and show up for reviews.


How a normal session feels

  1. Pick a topic
    Group cards by exam, project, standard, language, or whatever matches your life.

  2. See what’s due
    REVU builds a daily queue of cards that are just about to be forgotten and ones that are being consolidated for the long term.

  3. Answer from memory
    You see the front of the card, answer in your head (or out loud), then reveal the back.

  4. Tell the app how it felt
    You rate the card (easy / normal / hard). The scheduler uses that to push easy cards further out and bring hard ones back sooner.

Result: more retention per minute, with the app doing the calendar maths.


Capturing material that isn’t just plain text

REVU is built for messy real-world inputs, not just typed notes.

  • Images on front and back – attach one or many images to either side of a card: diagrams, screenshots, slides, whiteboard photos. They show inline during review and can be opened full-screen with zoom and swipe.
  • OCR for screenshots & slides – REVU can read text out of images using Apple’s Vision framework, so your slide becomes a searchable, reviewable card instead of just a picture.
  • “No text found? Explain it once.” – if OCR can’t extract anything useful, the app prompts you to write or dictate a short explanation before saving, so every card is actually reviewable later.
  • Dictation for answers and card creation – use speech recognition when typing is annoying; REVU converts your voice to text on-device.

All of this is wrapped in a card editor and review UI that’s tuned for light/dark mode, accessibility, and not getting in your way.


Review engine and AI options

At the core is the review session:

  • Cards are scheduled with SM-2 / FSRS-style algorithms tailored per card and per topic.
  • A dedicated ReviewSessionView tracks results, correctness and next-review dates, feeding into long-term stats and insights.

For answer checking you can choose:

  • Apple AI – runs entirely on your device; card content stays local.
  • ChatGPT (OpenAI) – if you enable it, REVU sends only the question and your answer to the API to judge how close you were. No extra personal profile data is attached.

You can switch engine at any time from Settings.


Sync, offline use, and background behaviour

REVU is designed to behave like a serious productivity tool, not a toy.

  • Local first – everything is stored in a Core Data database on your device. If you’re offline, you can still add cards, attach images, and review normally.
  • Private iCloud sync – if you turn sync on, cards, topics, reviews and attached images are mirrored to your private iCloud database using Apple’s NSPersistentCloudKitContainer. Erin Consulting never sees this data.
  • Conflict-aware – if you edit the same card on two devices, REVU uses timestamps to merge text and images so you don’t end up with broken cards or orphaned media.
  • Image limits that respect your storage – individual images are capped and there’s a total per-user budget, with graceful failure if you hit the limits, to stay GDPR- and sanity-friendly.

Background sync uses Apple’s background refresh tasks to upload changes in small, throttled batches so your battery doesn’t hate you.


Notifications that behave like a good citizen

Review reminders are best-effort nudges, not spam:

  • Requested only when you enable reminders – never on first launch.
  • Capped to a small number of notifications per day, with a minimum gap between them to avoid being throttled by the OS or annoying you.
  • Respect Focus modes, Do Not Disturb, system summaries, and OS throttling – REVU does not try to bypass system rules.
  • Automatically cleaned up when you clear all due cards, so you don’t see stale “review now” banners after you’re already done.

If notifications are disabled at system level, the app stops scheduling them and explains what’s going on instead of silently failing.


Privacy, security, and control

REVU is built with data-minimalism as a feature:

  • Core data (cards, topics, reviews, images) live on your device and, if you choose, your private iCloud space.
  • Answer-checking with ChatGPT is strictly opt-in and limited to the card’s text and your answer – nothing else.
  • A dedicated security layer manages encryption and secure storage for sensitive bits like identifiers or tokens.
  • You can export your data and request full deletion from within the app’s Settings.

Full details live in the Privacy Policy and Terms of Service linked from the site and from inside the app.


Plans and subscriptions

REVU has a free tier and optional upgrades handled entirely by Apple’s in-app purchase system:

  • Entitlements (what your plan unlocks) are stored with your user profile so they sync across your devices.
  • Subscription metadata such as product ID and expiration are stored alongside the user entity, so the app can behave predictably when a plan changes or expires.

Apple handles all billing and refunds; REVU just enforces what your current entitlement allows.


Who REVU is for

REVU is aimed at people who:

  • Sit professional exams or certifications and need knowledge to stick
  • Work in fields with complex standards or procedures (engineering, medicine, finance, software, safety, compliance)
  • Learn languages or long-term skills where forgetting is expensive
  • Want a spaced-repetition system that behaves like a well-engineered product, not a pile of scripts and hacks

If that sounds like you, REVU is meant to be the quiet little engine that keeps your long-term memory tuned while you get on with the rest of your life.