Comparison

Japsum vs Index Sums

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

Head to head
About

Japsum

Features
Read full description

Japsum (short for "Japanese Sum") is a free, logic-based, combinatorial number-placement puzzle game. It’s similar to Kakuro or Sudoku puzzles, but with its own unique twist. Starting with an empty grid, you’ll use hints provided on the sides and top to place numbers or black boxes in the grid. The hints indicate the sums of consecutive numbers, with no black boxes in between. Multiple hints mean that sequences of numbers are divided by one or more black boxes. By using logical reasoning and interpreting these hints, you’ll make steady progress in filling in the grid with numbers and black boxes. Be prepared—especially with the larger grids, these puzzles can get very challenging! The app offers grid sizes ranging from 3x3 to 22x22—the largest puzzles of this kind, as far as I know. Every puzzle has exactly one unique solution, ensuring a fair and rewarding challenge. As you solve puzzles, your level increases, unlocking larger grids and fun bear avatars that you can choose to represent your progress. Best of all, Japsum is completely free—so you can dive into the world of Japanese Sum puzzles at no cost. Are you ready to test your logic and take on the ultimate puzzle challenge? Download Japsum today and start solving!

About

Index Sums

Engage your mind with a Japanese number logic puzzle. Fill grids based on row and column sums, using pure logic to reveal hidden patterns. Offers multiple difficulty levels and daily challenges for continuous mental stimulation.

Highlights
  • Row and column sum logic puzzles
  • Multiple difficulty levels
  • Daily challenges
  • Progress tracking and statistics
  • Offline play
  • Customizable themes
  • Haptic feedback
Features
Read full description

Challenge your mind with Index Sums (Kakurasu), an elegant Japanese number logic puzzle that combines the best of Sudoku and Nonograms! HOW TO PLAY: • Fill in the grid based on row and column sums • Use logic to determine which cells should be filled • Complete the puzzle to reveal a hidden pattern • No guessing required - pure logic and deduction! KEY FEATURES: • Multiple difficulty levels (Easy, Medium, Hard) • Daily challenges to keep your mind sharp • Track your progress and statistics • Beautiful, minimalist design • Dark mode support • Offline play capability • Customizable themes and colors • Haptic feedback for better interaction BENEFITS: • Mental Agility: Challenge your logical thinking and problem-solving skills • Focus & Concentration: Practice maintaining focus through engaging puzzles • Pattern Recognition: Develop your ability to spot patterns and make quick decisions • Stress Relief: A relaxing way to unwind while keeping your mind active • Daily Challenge: Build a fun routine with daily puzzles • Progress Tracking: Monitor your improvement over time GAME MODES: • Classic Mode: Solve at your own pace • Daily Puzzles: New challenges every day • Practice Mode: Learn the basics FEATURES: • Intuitive touch controls • Haptic feedback • Progress tracking and statistics • Level progression system • Share your achievements • No ads or interruptions • Regular updates with new features Whether you're a puzzle enthusiast or looking to improve your logical thinking, Index Sums offers the perfect blend of challenge and satisfaction. Download now and join thousands of players in this addictive number logic puzzle!

Screenshots

Japsum4 screens
Index Sums4 screens

Verdict

The call

The clearest difference is iOS requirement: Japsum at 9.0 against Index Sums's 17.6. On price, ads, in-app purchases 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Scorecard1 real difference · 9 level
Japsum versus Index Sums: the parameters behind the verdict, then further details
ParameterJapsumIndex Sums
PriceFreeFree
Rating—5.0 (3 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—3 — better
Update frequency—Every 3 weeks
AdsNoNo
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS9.0 — better17.6
Further details — not scored
Size121 MB25 MB
Age rating4+4+
DeveloperJENS WOLF WEIGELZORIX LLC

In-app purchases

None

Japsum

No in-app purchases

None

Index Sums

No in-app purchases

Questions

Is Japsum free?
Japsum is free to download, with no in-app purchases.
Is Index Sums free?
Index Sums is free to download, with no in-app purchases.
Do Japsum or Index Sums have ads?
Neither Japsum nor Index Sums shows ads.

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