A flashcard app for learning that lasts
Study quietly.
Remember everything.
JustFlip! is the spaced-repetition flashcard app that lives quietly across every Apple device you own. Curate decks on the Mac, review them on iPhone or iPad — or rate a card from your wrist, without reaching for your phone. An SM-2-inspired engine surfaces the right card at the right moment.
What you can check for yourself
- A native Apple app Built for iOS, iPadOS, macOS and watchOS — not a web page in a wrapper.
- Offline by default Decks, reviews and the scheduling engine all run on device. iCloud only syncs.
- Nine languages The whole app — and this very page — fully localized, not machine-guessed.
- A published accessibility report What is implemented, what is measured, and what is still open. →
A closer look
See JustFlip! in action.
Take a quick tour of the calm, focused way JustFlip! helps you learn across all your Apple devices.
One library.
Three companions.
Capture and curate on the Mac. Review on the iPhone over morning coffee. Annotate on the iPad in the margins. iCloud keeps every card, every interval and every streak in perfect sync — without ever asking you to think about it.
Let the AI write the deck.
Two ways to create decks — full rich-content cards with agentic coding tools, or simple text-only sets directly in ChatGPT.
A library you can swipe through.
Browse decks as a calm, editorial list — or enter a focused review and judge each card with a Tinder-style swipe — right for good, left for hard, up for easy, down for again — or tap the same four buttons. The flow stays in your hand.
A patient algorithm.
Five states. Lasting recall.
JustFlip! runs a refined SM-2 engine across five learning states. Cards travel through unseen, learning, reviewing, relearning and graduated, each with its own interval and ease. Urgency tells you what is most worth your time today.
- UnseenNever studied — ready for first contact.
- LearningMinutes to a day. Fresh memory taking shape.
- ReviewingDays to weeks. The interval grows by ease.
- RelearningForgotten? Back to short intervals, gently.
- GraduatedWeeks to months. Long-term retention.
Ease grows on easy, settles on good, and contracts on hard or again — never below 1.3.
Not just flipping cards.
A proven way to remember.
Decades of memory research — popularized in the bestselling book Make It Stick: The Science of Successful Learning — point to one conclusion: we remember by retrieving, not rereading, and by spacing practice over time. JustFlip! turns that science into a daily habit.
Each review lifts recall and flattens the curve of forgetting.
Recalling beats rereading
Every card asks you to pull the answer from memory before you flip — that effort is what makes it stick.
Let a little forgetting work for you
Reviews return just as memory starts to fade, when each repetition does the most good — the SM-2 engine's quiet job.
Mix it up
Shuffling topics in one session feels harder — and builds memory that lasts far longer than studying in blocks.
A worthwhile struggle
Judging each card Again, Hard, Good or Easy keeps reviews honestly challenging — the kind of effort that deepens learning.
“Learning is deeper and more durable when it's effortful.”
— Make It Stick: The Science of Successful Learning
Ready to try it?
Five honest minutes, tonight.
Start with a single deck and let the engine decide when it comes back to you.
Cards that read like essays.
Define your cards in rich Markdown — headings, lists, code blocks, inline math, images and links. JustFlip! renders them with editorial typography so a card can be a one-line cue or a small piece of scholarship.
Decks that speak.
Let your cards read themselves out loud while you walk, cook, or drive. A Live Activity on your Lock Screen keeps the playback in sight — a small, golden invitation to five minutes of practice.
Your day, at a glance.
Open your Mac and JustFlip! greets you with today's review — what's due, what's new, and a single warm tap to begin. On iPhone and iPad, Lock Screen and Home Screen widgets keep your due count, your streak and your week's rhythm a glance away — so the next five minutes are never more than a look from where you already are.
Open to what matters
The Mac welcomes you with today's review — a daily amount that adapts to how much you actually learn — and starts the session in a single tap.
A glance before you unlock
Cards due and your running streak sit quietly on the Lock Screen, nudging you toward five honest minutes.
A week at a size that fits
A Home Screen widget charts your week, so progress stays in view between everything else you opened the phone for.
On your wrist, too.
Feel the tap, glance down, rate the card — the same spaced-repetition engine, three inches from your pulse. Turn the Digital Crown to keep reading; a firm press marks it Again, Hard, Good or Easy. No phone required.
Dark by candlelight.
Light by morning.
JustFlip! respects the system. Switch from a deep, scholarly dark to a soft parchment light — the gold and slate stay true at any hour.
Learning, for every learner.
JustFlip! is being built to work with the tools people rely on. Our accessibility report separates implemented support from the device validation still to come.
VoiceOver, close to ready
Semantic coverage is implemented across the main flow; device validation is the remaining step.
Cards that speak
Text-to-speech reads your cards aloud for eyes-free, low-vision and dyslexia-friendly study.
Larger Text
Card content, controls and constrained layouts now scale with the system text size.
Beyond color alone
Learning states use labels and position; symbols and shapes add extra cues. Contrast is still being measured.
Speaks your language
The whole app — and this very page — is localized into nine languages.
English · Deutsch · Español · Français · Italiano · Português · 日本語 · 한국어 · Čeština
Available now on Mac, iPhone, iPad and Apple Watch
Bring JustFlip! to your shelf.
One purchase. Three platforms. A lifetime of well-spaced review.
Available in English, Deutsch, Español, Français, Italiano, Português (Brasil), 日本語, 한국어 & Čeština.