Zero Deficit vs BrainRock
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Zero Deficit
Prepare for your CCRN exam with a comprehensive study tool built by an ICU nurse. It offers over 695 practice questions with detailed rationales, AI-powered personalization, smart flashcards, and full-length simulation exams to identify and address knowledge gaps.
- 695+ high-yield practice questions
- Detailed rationales for every question
- AI-powered personalized study guides
- 190+ smart flashcards with spaced repetition
- Full-length simulation exams
- Detailed performance analytics
- Exclusive cheat sheets
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Pass the CCRN exam with Zero Deficit — critical care nursing certification prep built by ICU nurses who actually passed. EVERYTHING YOU NEED TO PASS • 695+ CCRN practice questions with detailed rationales, covering every body system on the AACN exam blueprint • 8 in-depth study guides weighted exactly like the real exam: Cardiovascular (17%), Respiratory (15%), Multisystem (14%), Neurology (12%), Renal, GI, Endocrine, Hematology • 200-question timed CCRN exam simulation with scoring and a readiness level • Two 100-question practice quizzes to build test-day stamina • AI-powered question generator that creates fresh questions tuned to your weak areas • Spaced-repetition flashcards based on cognitive science • High-yield cheat sheets and question-breakdown strategy training ICU CLINICAL REFERENCE • 77-medication ICU drug reference: vasopressors, sedation, anticoagulants, antiarrhythmics and more — with typical dose ranges • Hemodynamic monitoring guide: normal values, PA catheter waveforms, shock profiles • Shock, ABG and arrhythmia flowcharts for rapid review STAY ON TRACK • Exam countdown with readiness tracking • Daily question notifications that keep your streak alive • Progress analytics by body system so you always know where to focus • Study streaks, achievements and a weekly leaderboard BUILT FOR ICU NURSES, BY ICU NURSES Every feature came from real feedback during the 30 most stressful days before exam day. 12-hour shift followed by a 2-hour study session? We built the app we wish we'd had. STUDY ANYWHERE Print any study guide as a clean, formatted PDF for break-room review. All 8 body-system study guides and their quizzes are free — no account required. WHO USES ZERO DEFICIT • ICU registered nurses preparing for AACN CCRN (Adult) certification • CVICU, MICU, SICU, NSICU and CCU staff • ER nurses transitioning to critical care • Travel nurses studying between assignments • Nurse managers earning the CCRN to stay clinical SIMPLE PRICING Free: all 8 body-system study guides + system quizzes. A free account starts a 3-day full-access trial — no credit card required. Go premium with Monthly, Yearly or Lifetime access (auto-renewable subscription or one-time lifetime purchase) to unlock the full question bank, exam simulation, cheat sheets, ICU drug reference and flashcards. Content is written and source-checked against FDA labels and major clinical guidelines (AHA/ACLS, Surviving Sepsis Campaign, SCCM). Educational material — not medical advice. CCRN® is a registered trademark of AACN Certification Corporation. Zero Deficit is an independent study platform and is not affiliated with or endorsed by AACN.
BrainRock
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Learning a language should feel simple—not like homework. Tell BrainRock what you want to learn: travel phrases, everyday conversation, work, exams, or a hobby. AI instantly creates a vocabulary pack matched to your level, with useful examples and clear pronunciation. No deck building. No overwhelming lessons. Just a few useful words at a time. WHY BRAINROCK FEELS EASY • Learn words you actually want to use • Start in seconds from a topic or photo • Listen and repeat with audio pronunciation • Lock in memory with quick quizzes • Keep momentum with daily review reminders • Watch your progress grow as you level up PERFECT FOR Travel, conversation, TOEIC, TOEFL, JLPT, HSK, TOPIK, DELE, business, and everyday vocabulary. Pick a topic. Learn for a few minutes. Come back tomorrow. Small sessions turn into real progress. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://rockparks.com/brainrock/privacy.html
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Verdict
The clearest difference is in-app purchases: BrainRock at none against Zero Deficit's 3. On price, update cadence, ads and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Zero Deficit sells 3 in-app purchases, starting at $14.99 per month. BrainRock asks for nothing beyond the download.
Both ship on a similar rhythm, roughly weekly. The most recent releases landed on October 10, 2026 and October 5, 2026 respectively.
| Parameter | Zero Deficit | BrainRock |
|---|---|---|
| Price | Free | Free |
| Rating | 5.0 (4 ratings) — better | — |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | 4 — better | — |
| Update frequency | Weekly | Weekly |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.0 | 15.0 |
| Further details — not scored | ||
| Size | 3 MB | 164 MB |
| Age rating | 12+ | 4+ |
| Developer | ZERO DEFICIT LLC | HAYOUNG KOH |
In-app purchases
Zero Deficit
- Zero Deficit CCRN PREP MONTHLY3 Days trial$14.991 Month
- Zero Deficit CCRNPrep PremiumAnnual$84.991 Year
- Zero Deficit CCRN Prep Lifetime$199.99
BrainRock
No in-app purchases
Questions
Is Zero Deficit free?
Is BrainRock free?
Do Zero Deficit or BrainRock have ads?
Which is updated more often, Zero Deficit or BrainRock?
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