Comparison

ProblemSum vs Learn Korean

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

Head to head
About

ProblemSum

Practice math word problems aligned with the Singapore Mathematics syllabus for Primary 6 students. Get detailed solutions for each problem. The app works offline and requires no account.

Highlights
  • Random math word problem generation
  • Singapore Math syllabus alignment
  • Detailed step-by-step solutions
  • Offline functionality
  • No account required
  • Ad-free experience
Features
Read full description

ProblemSum — unlimited PSLE problem sums, every one fully worked. PSLE word problems: ratio, fractions, percentage, money, algebra, rate, time, number patterns and more. Not geometry figures, charts or patterns drawn as shapes — those are read off a picture, and this app writes questions. Primary 6 maths practice that never runs out — because there is no question bank to run out of. No account. No subscription. No internet connection. Pay once and it is yours. NOT A QUESTION BANK Most practice apps ship a fixed set of questions. Work through them and you are done; work through them twice and your child is remembering answers instead of solving problems. ProblemSum has no such list. Every question is written when you ask for it, with its own names, numbers and quantities, and the working follows those numbers — so there is no end of the book to reach, and no set of answers to fall back on instead of the method. AND EVERY ONE IS WORKED THROUGH Type your answer, tap Check Answer, and the full solution opens underneath: the bar model drawn out, the units labelled, every line of working, and — on most questions — a check at the end proving the numbers really do add up. Most types also offer a second method, so a child who cannot see the model can follow the working through instead, or the other way round. BAR MODELS, DRAWN PROPERLY The model method is how Singapore classrooms teach these problems, so it is how ProblemSum explains them. Bars are drawn to scale with their units marked, the part that changed hands shaded, and braces showing what is left — drawn for the numbers in front of you. SOLUTIONS SET LIKE A TEXTBOOK Working is laid out the way it would be written on paper: fractions stacked over their denominators, ratios and percentages and money in their proper forms, and units carried through every line. BUILT FOR THE 2026 SYLLABUS Algebra is new to Primary 6, and it is here, with circles, three-term ratio, volume worked backwards, dividing by a fraction and percentage change. So is the earlier content the PSLE still examines: time and the 24-hour clock, factors and multiples, number patterns, area and perimeter, and discount, GST and interest. Rate comes as the charges a paper sets — by the hour, and in bands — and averages change as someone joins or leaves. WHAT IT COVERS, AND WHAT IT DOES NOT Ratio and fractions run deepest, then percentage and money, then volume and capacity, then algebra, average, rate, rate of work and whole numbers, with age, area and perimeter, circles, factors and multiples, mass, measurement, number patterns and time each drilled by their own kind of question. Every one is set at PSLE level. What it does not do: geometry from a figure, charts and graphs, and patterns drawn as shapes. Those are read off a diagram rather than a paragraph, so they sit outside what a word-problem generator can write. The Info tab lists both sides of that line, so you always know what you have. ANSWER IT THE WAY YOU THINK OF IT $4.50 or 4.50. Three-quarters as 3/4 or 0.75. A time as 1.45 p.m. or 1345. A ratio with spaces or without. ProblemSum accepts the formats a Primary 6 child actually writes, so a right answer is never marked wrong for its punctuation. COME BACK TO WHAT YOU HAVE DONE Recent questions stay on the device with their full solutions, ready to open and read through again. ONE APP, EVERY LEARNER Set up a profile for each child. Each one keeps its own score — questions attempted, questions right — so two children can share an iPad without sharing a total. IPHONE, IPAD AND MAC One purchase covers all three. On Mac and iPad with a keyboard, Command-N gives you the next question and Command-Return checks your answer. WORKS ANYWHERE, TELLS NO ONE ProblemSum makes no network connections at all. There is no account to create, no analytics, no advertising and no data collection of any kind — everything is generated on the device and stays there. Built for the Singapore syllabus.

About

Learn Korean

Master Korean vocabulary and Hangul recognition with this interactive app. It features over 5,700 essential words from TOPIK I & II, native pronunciation, and an engaging learning system designed for all levels.

Highlights
  • Master 5,700+ TOPIK words
  • Learn Hangul characters
  • Active recall learning
  • Native Korean pronunciation
  • Engaging sound effects & graphics
  • Interactive learning experience
Features
Read full description

Make 5,700 Korean words stick. Hangul Hero turns every TOPIK I and TOPIK II word into a fast recognition game you'll actually keep playing — the same Hero Method that has taught Chinese learners since 2016, built for Korean. Free to try. WHY IT WORKS Flashcards show you a word and ask "do you know this one?" It's too easy to nod along. Hangul Hero makes you do the work: you get the English meaning, the romanization, or both, you can tap to hear the word, and then you have to find its syllables on a grid of Hangul drawn from the same level — 학, then 교, and you've built 학교. Switch to English-only prompts and you must produce the Korean word in your head before you can spot it. That's recall, not just recognition, and it's what gets you reading Hangul without the crutch. DIAL THE DIFFICULTY UP OR DOWN • Prompt with the English meaning, the romanization, or both • Play on a 2×2, the classic 3×3, or a 4×4 grid • Turn on Assist Mode if Hangul is brand new to you • Jump to any level, TOPIK I through TOPIK II, whenever you like EVERYTHING FOR TOPIK I AND II • All 5,700 words of the TOPIK I and TOPIK II vocabulary, organized by level • Tap to hear every word spoken aloud, at learner speed • Romanization and English definitions for every word • Works offline: study on the plane, the subway, or the walk to class • Beautifully rendered Hangul • No ads, no account, no data collection WHO IT'S FOR • TOPIK candidates who need the vocabulary automatic before exam day • Beginners who want to read Hangul instead of leaning on romanization • Intermediate learners closing the gap between TOPIK I and TOPIK II • Anyone who has abandoned a flashcard app out of boredom GOOD TO KNOW Complete beginner? Yes, it's for you: start at the first level, turn on Assist Mode and keep both prompts on until you're ready to make it harder. Writing practice or a dictionary? No. Hangul Hero does one job, making you recognize and recall Korean words fast, and does it well. Which TOPIK? The complete TOPIK I and TOPIK II vocabulary: 5,700 words. Who makes it? A small independent studio that has kept HSK Hero on the App Store since 2016 and Hangul Hero since 2020. What does it cost? The first group of levels is free. If it clicks, one purchase unlocks all 5,700 words for good. No subscription. Pick your level and see how far the Hero Method takes you. 화이팅!

Screenshots

ProblemSum4 screens
Learn Korean4 screens

Verdict

The call

The clearest difference is review sentiment: ProblemSum at 100% against Learn Korean's 50%. ProblemSum also leads on in-app purchases (none vs 1) and update cadence (every 5 weeks vs every 14 months). Learn Korean's advantage is price (Free vs $2.99) and ratings volume (18 vs 1). On 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

CostPrice · In-app purchases · Ads · Monetization

Learn Korean is free to download; ProblemSum costs $2.99 up front. Learn Korean sells 1 one-off in-app purchase. ProblemSum asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

ProblemSum holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Learn Korean has 18 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 100% of ProblemSum's written reviews are positive against 50% of Learn Korean's.

UpkeepUpdate frequency

ProblemSum ships an update every 5 weeks, Learn Korean every 14 months. The most recent releases landed on October 3, 2026 and October 14, 2026 respectively.

Scorecard8 real differences · 2 level
ProblemSum versus Learn Korean: the parameters behind the verdict, then further details
ParameterProblemSumLearn Korean
Price$2.99Free — better
Rating5.0 (1 ratings) — better4.7 (18 ratings)
Positive reviews100.0% of reviews — better50.0% of reviews
Number of ratings118 — better
Update frequencyEvery 5 weeks — betterEvery 14 months
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaidFree with in-app purchases — better
DevicesiPhone, iPad, MaciPhone, iPad, iPod
Requires iOS18.015 — better
Further details — not scored
Size2 MB20 MB
Age rating+44+
DeveloperAeterna SolutionsHandtechnics

Customer experience

ProblemSum

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Learn Korean

All ratings18 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive50.0%
Neutral0.0%
Negative50.0%

In-app purchases

None

ProblemSum

No in-app purchases

1 purchases

Learn Korean

One-time1
  • Unlock Everything$39.99

Questions

Is ProblemSum free?
ProblemSum costs $2.99, with no in-app purchases.
Is Learn Korean free?
Learn Korean is free to download, with in-app purchases available.
Which has better reviews, ProblemSum or Learn Korean?
ProblemSum is rated higher. ProblemSum averages 5.0 out of 5 from 1 ratings, while Learn Korean averages 4.7 from 18 ratings.
Do ProblemSum or Learn Korean have ads?
Neither ProblemSum nor Learn Korean shows ads.
Which is updated more often, ProblemSum or Learn Korean?
ProblemSum ships an update every 5 weeks, and Learn Korean every 14 months. Most recently, ProblemSum was updated on October 3, 2026 and Learn Korean on October 14, 2026.

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