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For ICU nurses & CCRN candidates

Stay CCRN-sharp between shifts, five minutes a day

RecallOS turns CCRN prep into a short daily habit instead of a weekend cram. Each day you get a five-minute Recall Run across critical-care content domains — with a mini chest after each block and an instant rationale on every question. Built by a practicing CRNA, the daily run is free forever, and free users are never blocked from learning.

Try the free daily Recall RunDownload on theApp Store

The problem

ICU nurses rarely have a free hour to sit with a review book. You pick up a question bank the week before the CCRN, grind through a weekend, and most of it has faded by the next shift. Critical care is broad — hemodynamics, ventilation, sepsis, neuro, renal, endocrine, multisystem — and trying to hold all of it at once is exactly how it slips away. What actually sticks is short, spaced review you can keep up between 12-hour shifts.

How RecallOS helps

Five minutes fits a 12-hour shift

The daily Recall Run starts instantly and wraps in about five minutes — on a break, in the parking lot, or before handoff. It never blocks free users, so the habit is always there when you have a spare moment.

Spaced repetition handles the schedule

Active recall plus spaced repetition means you revisit the right concept at the right time. Mastery attaches to the concept, not one phrasing of a question, so it holds up when the wording changes on you.

Good misses come back tomorrow

Miss a hemodynamics question today and it folds into tomorrow's run automatically. Weak spots resurface on a spaced schedule until you own them — a good miss you master tomorrow, not never.

A Recall Score you can watch climb

Every run nudges your Recall Score, so progress across the critical-care domains is something you can see instead of a vague feeling that you should be studying more.

What you get

  • The daily Recall Run

    Fifteen questions a day — three critical-care blocks of five — with a mini chest after each block and a Daily Chest at the end. About five minutes, and free forever.

  • Instant rationales on every question

    Right or wrong, you get the why immediately. A good miss turns into a quick, high-yield lesson instead of a dead end.

  • Upload your own ICU notes

    Drop in your unit's slides, a PDF, or a photo of your notes (up to 10 MB) and turn them into a summary, study guide, flashcards, a practice quiz, or a concept map. One free preview, no signup.

  • Panic Mode for crunch week

    When the exam is close, Panic Mode builds a time-boxed cram plan so your last stretch is focused instead of frantic.

  • Between-shift streaks and weekly leagues

    Streaks, XP, gems, chests, badges, weekly leaderboards, friend challenges, Recall DNA, and daily missions keep a dry review habit genuinely fun to come back to.

  • A free 5-question starter

    Try RecallOS right now with a free NCLEX-style starter run — five questions, instant feedback, no account required.

A realistic daily workflow

  1. 1On a break, open RecallOS and tap into the daily Recall Run — a 10-question core across two critical-care sections of five.
  2. 2Answer each one and read the instant rationale, including on your good misses.
  3. 3Collect a mini chest after every block and a Daily Chest when you finish the run.
  4. 4Yesterday's good misses fold back into today's run, so weak spots get spaced repetition without you scheduling anything.
  5. 5Before a heavy study day, upload your ICU notes to spin up a study guide or a practice quiz in a couple of taps.

What RecallOS is (and isn't)

RecallOS is a daily active-recall companion for critical-care review — not a comprehensive question bank, not a course, and not a substitute for your unit's protocols or your own clinical judgment. Coverage is mapped to published critical-care content domains and is educational, not exhaustive. It is an independent study aid, not affiliated with or endorsed by the AACN Certification Corporation. It was built by a practicing CRNA to keep review sustainable — not to promise a score or a pass.

AI study aid — not medical advice
Generated by AI for educational use only. This is not medical, clinical, or professional advice and must not be used to make patient-care or treatment decisions. RecallOS is independent and not affiliated with, endorsed by, or sponsored by any board, certifying body, or licensing authority. Learn more

Frequently asked questions

Is RecallOS affiliated with the AACN Certification Corporation?
No. RecallOS is an independent study aid and is not affiliated with or endorsed by the AACN Certification Corporation. Content is mapped to published critical-care content domains and is meant to support your review — educational, not exhaustive.
How long does the daily run take, and is it really free?
About five minutes for the 10-question core. Five earns the day, ten opens the Daily Chest, and the optional Bonus Round never gates either reward.
Can I study my own ICU protocols and notes?
Yes. Upload notes, PDFs, slides, or a photo (up to 10 MB) and RecallOS turns them into a summary, study guide, flashcards, a practice quiz, or a concept map. You get one free preview with no signup.
What are Exam Predictions?
Exam Predictions are AI estimates meant to help you focus your studying on likely weak areas. They are not a guarantee of a score, a pass, or what will appear on your exam — treat them as a study aid, nothing more.
Do I pay on the website?
No. The website is for marketing and the free starter run only. Any purchase happens through Apple In-App Purchase inside the RecallOS iOS app — never a web checkout.
I'm a CCRN candidate also eyeing CRNA school — does this fit both?
It can. The critical-care habit carries over, and RecallOS supports an anesthesia-focused path for aspiring CRNAs and current SRNAs. See the CRNA / SRNA study app page for how that track differs.

Related resources

Start today's Recall Run

The daily Recall Run is free, forever. A few minutes a day — warm up your brain and stay sharp.

Try the free daily Recall RunDownload on theApp Store