We're the team behind Flips, a flashcard app built around the idea of showing you a word right before you forget it. We often hear that there are so many memorization apps, and store searches turn up so many similar-sounding descriptions, that it's hard to know which one to pick.
As people who actually build one of these apps, we'll be honest: whether a memorization app is good or bad is decided almost entirely by how well it follows how memory works — not by looks or the number of words it ships with. In this article, instead of listing app names, we'll explain five things to check that apply to any app you consider, along with why each one matters. At the end, we'll note how our own Flips measures up.
Check 1: Does it manage review timing automatically?
This is the most important one. People start forgetting the moment they learn (the forgetting curve), so memorization comes down to whether you can recall something right before you forget it. Managing that word by word by hand is impossible, so whether the app serves up review timing automatically based on the forgetting curve (i.e. supports spaced repetition) is the top priority to check. An app that just flips cards or shows them in order leaves this most important part for you to do.
Check 2: Does it let you learn by recalling?
What strengthens memory is recall (output), not looking (input). This is called active recall, and simply quizzing yourself has been shown to raise retention. So check whether it has a retrieval mechanism — hiding the answer and recalling it, or answering a quiz. An app that lets you put a recall load on yourself changes your results in the same amount of time compared to one you just stare at.
Check 3: Can you build your own decks?
Even a huge built-in vocabulary doesn't guarantee the words you want are in it. Exam terms, words from class, professional jargon — if you want to learn this kind of “content only you need,” whether you can freely create your own decks becomes important. Conversely, if you want to learn from ready-made sets, check whether decks that fit your goal are included. An app that does both can keep serving you even as your purpose changes.
Check 4: Is it designed to keep you going every day?
However feature-rich an app is, it's meaningless if you can't keep it up. What to check: can you move one question at a time in spare moments, does it notify you of review timing, is it light enough that you actually want to open it daily? Apps that are slow to launch, demand long sessions, or make you decide what to do every time will stall on a busy day. Sustainability is easy to overlook because it doesn't show up on a feature list, but it's the thing that decides your results.
Check 5: Is it easy to get started (cost and platform)?
The last one is ease of starting. Check whether you can try it for free and use it on your phone (iOS / Android). Since memorization is a long-term effort, the safe move is to confirm for free that it fits your study style before committing. If a paywall is required from the start, it's harder to switch away when it doesn't fit.
How Flips measures up against these five
When we designed Flips, meeting exactly these five was our goal. (1) Based on Ebbinghaus's forgetting curve, it calculates each word's review timing automatically (spaced repetition). (2) Card Mode (recall, then flip) and Quiz Mode (answer from four choices) are both forms of active recall. (3) Decks for English, Spanish, Chinese and more are built in, while you can also create your own. (4) You can move one question at a time in spare moments, and it notifies you of optimal review timing with a push notification. (5) It's free to start and works on iOS and Android.
What matters isn't “choosing Flips” — it's choosing by these five. We'd be glad if you used this article as a checklist whenever you evaluate any app, and even gladder if you tried Flips as one option that meets the criteria.
Flips
The flashcard app that shows you words right before you forget them. Forgetting curve, recall practice, custom decks, and notifications. Free to start.
Learn more about FlipsFrequently Asked Questions
Which check matters most when choosing a memorization app?
Check 1: does it manage review timing automatically (support spaced repetition)? Recalling right before you forget is the heart of memorization, and managing that yourself is hard in practice, so whether it's automatic strongly affects your results.
Is an app with more built-in words always better?
Not necessarily. What matters more than the count is whether the words you want are in it, and whether you can build your own decks. If you want to learn exam terms or jargon, an app that lets you create custom decks suits you better.
Should I choose a free app or a paid one?
The safe move is to start with something free and confirm it fits your study style. Since memorization is a long-term effort, judge after you've seen whether you can keep it up. Flips is free to start, too.
Why do some feature-rich apps still not stick?
Often they fail Check 4 — “designed to keep you going.” Sessions that are too long, slow launches, or having to decide what to do every time create friction that stalls you on busy days. A design where you can move one question at a time and today's batch is prepared automatically is easier to sustain.