Comparison

Crestellar Academy vs DSE MistakeBook

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Crestellar Academy

Features
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The all-in-one HKDSE Maths app for iPhone and iPad — 名校 exam questions, timed mock exams, past-paper solutions, revision notes, and every subject's 5** cutoff since 2012. Free to start, no account needed. DAILY PLAN • A short level check, then one free quiz a day aimed at your weak topics: easy first, no time limit, 5, 10 or 15 questions, a daily reminder, and offline once today's quiz is downloaded • After each quiz: your score, streak, level estimate and what improved • Shields and pauses protect your streak; My plan shows your level, calendar, topics and badges, secret ones too • Mark a Long Question "I got it" or "Not yet": your marks count towards your level and topics • Home Screen widgets: your streak and grade trend, an HKDSE countdown, or today's timetable JUPAS CALCULATOR • All 371 programmes at the eight UGC-funded universities and HKMU: admission scores, applications and offers back to 2012 (2026 for HKUST, CUHK, PolyU and HKMU; quartiles where published), tables of admitted students' subject levels where published, applicants per place, and official descriptions • Enter your HKDSE results: your score for 363 programmes, each under its own formula, and where you stand against the median — in 2024 too, where the formula is the same • Search, sort four ways and plan 20 choices in Bands A–E like the JUPAS form PRACTICE ENGINE • Thousands of MC and long questions from top HK schools — by year, topic and difficulty, plus an out-of-syllabus Challenging tier • Focused practice: almost every question is matched to the subtopic it mainly tests, and you choose which other subtopics it may use • Timed S1–S6 mock exams that mirror the real HKDSE Paper 2, slot by slot — your first 2 are free • Instant marking: a grade estimate, per-question review, per-topic time and accuracy • DSE LEVEL PREDICTOR: your mock score is graded on the REAL cut-offs of the last six HKDSE Maths exams, with how many more questions reach the next level • One-tap drill on your weakest topic • Long-question sessions of 5–50, unseen first • Save questions; share a result card 5** SOLUTIONS • Every question has a full marking-scheme solution — typeset, never a scan • Max plans unlock advanced solutions: faster 5** techniques, exclusive calculator programs, and Typical Questions & Skills for all 19 chapters WRITE ON THE QUESTION (iPad) • In quizzes, long and saved questions: pens, highlighter and eraser, pinned to the figure as it scrolls and zooms — or a scratch sheet • Hold at a stroke's end and it snaps perfect — lines, circles, polygons, parabolas — then drag its corners • Apple Pencil always draws and double-tap swaps to the eraser; workings are never stored VISUAL MATH LAB • 43 interactive topics — Compulsory Part (21), M1 (12) and M2 (13) — drag real DSE figures, watch the maths respond • AM–GM, Circle Angle Theorems, M2 Systems of Linear Equations and M1 Central Limit Theorem are free with no account; the rest are free to read — upgrade to interact REVISION TIMETABLE • Plan all 25 HKDSE subjects with official papers and topics: drag blocks, add reminders, or let "Build my week" fill your free hours; a Progress tab tracks mastery FREE TO START • No account needed: HKDSE cutoffs for 15 subjects since 2012, every programme in the JUPAS Calculator, and a question 30 seconds after download • A free account adds your daily plan, full past-paper solutions, illustrated revision notes, the revision timetable, your JUPAS score and choices, and 80 tokens a month FAIR PRICING • Top-up token packs that never expire • Plus, Pro and Max cost a fraction of one tutoring lesson • One subscription covers iPhone and iPad • Your plan stays with the phone number you bought it with Fully bilingual: English and Traditional Chinese. Built by Hong Kong DSE Maths teachers. Download free and aim for your 5**. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://www.crestellaracademy.com/privacy-policy

About

DSE MistakeBook

Features
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Turn wrong answers into marks on the next exam. Mistake Book is a private mistake journal for students. Photograph a question you got wrong, review it before you forget, and quiz yourself on your own errors — so the same slip does not cost you again. HOW IT HELPS YOU SCORE Exams reward what you can still recall under pressure. Logging every mistake, then coming back on a schedule, is one of the most reliable ways to raise your result. Mistake Book follows the forgetting curve (1, 3, 7, and 14 days) so you revise while the memory is still there to save. CAPTURE IN SECONDS • Take a photo, pick from your album, or type the question • On-device OCR for Traditional Chinese and English — then edit any line • Save the correct answer, your wrong answer, and why you missed it • Tag by subject, topic, and mistake type REVIEW BEFORE YOU FORGET • A due list for today — mark a question reviewed when you are done • Local reminders: daily when items are due, plus a weekly progress summary • Study quiz: up to 3 past mistakes, even if they are not due yet • Reveal the answer only after you have tried it in your head SEE WHERE TO WORK HARDER • Totals, this week, due vs up to date • Breakdowns by subject and mistake type • Share a summary card when you want a snapshot of your progress YOUR DATA STAYS ON THIS IPHONE No account. No upload. Camera and Photos are used only to capture questions on this device. Export a ZIP backup from Settings, or import one to restore your library. Built for students who study in English and Traditional Chinese — keep every mistake in one place, and walk into the next exam better prepared.

Screenshots

Crestellar Academy4 screens
DSE MistakeBook4 screens

Verdict

The call

The clearest difference is in-app purchases: DSE MistakeBook at none against Crestellar Academy's 10. Crestellar Academy's advantage is update cadence (weekly vs every 2 weeks). On price, ads, device support and iOS requirement 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Crestellar Academy sells 10 in-app purchases, starting at $4.99 per month. DSE MistakeBook asks for nothing beyond the download.

UpkeepUpdate frequency

Crestellar Academy ships an update weekly, DSE MistakeBook every 2 weeks. The most recent releases landed on October 30, 2026 and October 31, 2026 respectively.

Scorecard2 real differences · 4 level
Crestellar Academy versus DSE MistakeBook: the parameters behind the verdict, then further details
ParameterCrestellar AcademyDSE MistakeBook
PriceFreeFree
Update frequencyWeekly — betterEvery 2 weeks
AdsNoNo
In-app purchasesYesNo — better
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.617.0 — better
Further details — not scored
Size85 MB2 MB
Age rating12+4+
DeveloperCrestellar Academy LimitedYin Man Cheung

In-app purchases

10 purchases

Crestellar Academy

Subscriptions8
  • Plus$4.991 Month
  • Pro$9.991 Month
  • Max 5x$14.991 Month
Show 5 more
  • Max 20x$34.991 Month
  • Plus$49.991 Year
  • Pro$99.991 Year
  • Max 5x$149.991 Year
  • Max 20x$299.991 Year
One-time2
  • 500 Tokens$5.99
  • 2,000 Tokens$19.99
None

DSE MistakeBook

No in-app purchases

Questions

Is Crestellar Academy free?
Crestellar Academy is free to download, with in-app purchases available.
Is DSE MistakeBook free?
DSE MistakeBook is free to download, with no in-app purchases.
Do Crestellar Academy or DSE MistakeBook have ads?
Neither Crestellar Academy nor DSE MistakeBook shows ads.
Which is updated more often, Crestellar Academy or DSE MistakeBook?
Crestellar Academy ships an update weekly, and DSE MistakeBook every 2 weeks. Most recently, Crestellar Academy was updated on October 30, 2026 and DSE MistakeBook on October 31, 2026.

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