Acumo
The English words and phrases you keep mixing up.
Most vocabulary apps teach words you already half-know. Acumo works on the pairs that actually trip you up: adverse and averse, imply and infer, discreet and discrete. Open any word and it shows you what you will confuse it with and the one line that separates them, then drills the pair until the difference sticks. Built for B2 to C2, free to use, no ads, no subscription, and it works entirely offline.
Free
A complete app, not a trial- The whole confusable engine: what you will mix a word up with, why, and the one line that tells them apart
- Meanings in plain English, written against a 2,800-word defining vocabulary, so the explanation is never harder than the word
- A real example sentence on every entry, with the collocations that go with it: make a decision, not do a decision
- A short gloss in Persian, Spanish, Brazilian Portuguese or Arabic beside every entry, in the language you pick first
- Four card types, including discrimination: choosing between two confusables in context
- Search and manual add, plus the share extension on iPhone and iPad, so a word Acumo does not have still ends in an action
- Ready-made collections, your own list, and drills you can leave and pick up where you stopped
- VoiceOver, Dynamic Type and right-to-left support throughout, on iPhone, iPad and Mac
- Fully offline: no account, no network, nothing to sign up for
Pro
One-time purchase, no subscription- Spaced repetition that brings each item back on the day you are about to forget it: the FSRS algorithm, as used by Anki
- Weak-item targeting, so a session drills what you keep getting wrong rather than what you already know
- Progress and retention: your real retention rate, and the pairs you keep confusing
- On iPhone and iPad, a due count on the Home Screen widget, and grading a card without opening the app
- Every gloss language beyond your first, shown together on the same entry
- Anki-compatible export, plus backup and restore, so your list survives a new phone
Pro buys the retention system and the extra languages, never the English collection or the confusable engine. Pay once, with no renewals and no ads, tied to your Apple ID so you can restore it after reinstalling.
Built on confusion
Every kind of mix-up drives the app: homophones, near-homophones, look-alikes, prefix pairs, usage traps and phrasal-verb families. That is the product, not a feature bolted onto one.
Not a dictionary, not for beginners
Written for B2 to C2. No streaks, no XP, no cartoon mascot. Nuance is the whole point, so the app talks to you like an adult, not a beginner.
Private and offline
No account, no tracking, no data collected. The entire collection ships inside the app and everything runs on your device.
One fair price
Free is complete, not crippled: the confusable engine is never for sale. Pro is one purchase, never a subscription.