# Balconia Math : 21 Marbles — Logic puzzle for kids & adults > Logic puzzle game for kids and adults focusing on number reasoning. (iPhone/iPad app by Elitza Maneva.) - Source: https://appshunter.io/ios/app/balconia-math-21-marbles/id1347885940 (this page in markdown: same URL + `.md`) - Developer: [Elitza Maneva](https://appshunter.io/developer/1347885939) - Category: Games, Education, Board, Puzzle - Price: $0.99 - Rating: 4.45/5 from 146 App Store ratings · 13 written reviews indexed - Age rating: 4+ - Requires: iOS 8.0 · 49 MB - Languages: Basque, Bulgarian, Catalan, Czech, Dutch, English, Finnish, French, German, Hebrew and 16 more - Released: 2018-03-21 - Data updated: 2026-06-10 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/balconia-math-21-marbles/id1347885940/reviews.md ## What is Balconia Math? Try a new kind of math game in line with the Math Revolution envisioned by innovators like Youcubed and AOPS. Designed especially for children 6-11, "21 Marbles" doesn't quiz or time the player, instead it let's them enjoy thinking and reasoning. A puzzle game's level progression is a natural "low floor, high ceiling" exercise. In the case of 21 Marbles, while the puzzles can become challenging enough to be enjoyed even by adults, the game has a friendly progression of difficulty that keeps everyone on board. For the youngest players, it has the additional benefit of practicing the most basic arithmetic facts in an instinctive way. For the adults, it's like a relaxing peg solitaire game. There are no instructions because the rules are natural and intuitive. 21 marbles - of colors and designs for all tastes - are won one by one. In every level, the recovered marbles - each representing the number 10 - break randomly into pairs of smaller marbles: either into a 9 and a 1, or an 8 and a 2, or a 7 and a 3, or a 6 and a 4, or two 5s. The marbles get positioned randomly on a board, and can be merged back together into 10s, by knocking together pairs that sum to 10. It is always possible to recover all 10s, but some thinking ahead is required. The "undo" button is always there to let you trace back your steps and find your mistakes. Learning to think ahead is not optional, and is the most important educational aspect of this game. ## Key features - Logic puzzle gameplay - Number reasoning challenges - Intuitive, no-instruction rules - Progressive difficulty for all ages - Encourages forward-thinking - Arithmetic fact practice ## Recent user reviews (10 of 13) All indexed reviews: https://appshunter.io/ios/app/balconia-math-21-marbles/id1347885940/reviews.md ### 3/5 — Hmmmm… *2022-01-29, version 2.0.1* I loved playing this game…it really worked my brain.I was playing this game on a car ride and by the end of the car ride I had already done all 21 levels of the game and was so sad because it was so fun.I wish there were more levels!!!! ### 5/5 — Educational and fun *2019-09-16, version 2.0.1* A great way to learn while having fun. Child-friendly, no ads. ### 5/5 — 21 Marbles *2019-04-22, version 2.0.1* Addicting! As you progress, the game gets more tricky and challenging. ### 5/5 — 잘했네요. *2019-02-24, version 2.0.1* 무료로 풀려서 잘했네요. ### 3/5 — Cute, but *2019-01-21, version 2.0.1* Should have more levels ### 4/5 — Disappointed *2019-01-21, version 2.0.1* You should be able to play more than twenty one levels. ### 4/5 — Shucks. Does it really stop at 21? *2018-09-23, version 2.0.1* It was just getting good! Of course game seems designed for kids, and as an adult, I have an advantage. The challenge level improves as the numbers get higher. **Developer response:** Thank you for your feedback! I am thinking of an infinite-play version to be added to a future update, so don't delete the game just yet (or check back later). ### 5/5 — Fun *2018-09-22, version 2.0.1* Nice game. No pressure. ### 5/5 — Wonderful Game *2018-09-06, version 2.0.1* Of course it is 5 stars‼️It should be six. It is an excellent little game. ### 5/5 — Relaxing and challenging *2018-07-06, version 2.0* I’m always looking for unique and challenging games. Here, I found a challenge that allowed me to relax into it. Highly recommended! ## Frequently asked questions about Balconia Math ### What is Balconia Math: 21 Marbles? Balconia Math: 21 Marbles is a logic puzzle game designed to encourage reasoning and strategic thinking. It presents players with a board of marbles that can be merged to form sums of ten, requiring players to think ahead to solve each level. The game is suitable for both children and adults. ### How does the marble merging work? Marbles representing the number 10 break into pairs that sum to 10 (e.g., 9 and 1, 8 and 2). Players can merge these smaller marbles back into 10s by knocking together pairs that sum to 10. The goal is to recover all the 10s on the board, which requires planning and foresight. ### Is this game suitable for children? Yes, the game is specifically designed for children aged 6-11, offering a friendly progression of difficulty. It helps them practice basic arithmetic facts in an instinctive way while developing their problem-solving skills. Adults can also enjoy the challenging puzzles. ### What are the educational benefits of this game? The primary educational benefit is the development of forward-thinking and reasoning skills. Players learn to plan their moves and understand the consequences of their actions. It also provides practice with basic arithmetic facts in an engaging and intuitive manner. ### Is there a cost to play Balconia Math: 21 Marbles? Based on the provided information, the game is available for free. There are no in-app purchases or advertisements mentioned, suggesting a completely free gaming experience. ## Version history (last 5 releases) ### 2.0.1 — 2018-07-06 This app has been updated by Apple to display the Apple Watch app icon. Sharing your progress with friends is now a click away. Actually, a click and a parental gate away, to be exact. ### 2.0 — 2018-06-20 1. MUSIC! We have added two kinds of music - wind and string tunes with their corresponding marble-merging sounds. Now you can noodle on the saxophone while you are solving your puzzles. Of course, you can always choose to turn off the music and/or sounds. 2. By popular demand we have now made it possible to play the unlocked levels in any order, so that you do not have to start from 1 if you want to repeat the game. Also, since many grown ups find that the game starts out too easy for them, they can skip directly to level 7 from the beginning. 3. GDPR. Of course we haven't forgotten to comply with GDPR. You can now opt out of the data collection that Unity Analytics performs for us. For our case this includes basically your country, how long you play, and the levels you complete. We hope you don't opt out of data collection so that we can stay motivated to make new games. ### 1.1.3 — 2018-05-07 Minor modification. Change of category from "Education" to "Game: Board/Puzzle". ### 1.1.2 — 2018-04-30 Only very minor changes in the game. My age recommendation has changed to 9-11 instead of 6-8. ### 1.1.1 — 2018-04-27 Minor bug fixes. ## Apps similar to Balconia Math | App | Rating | Price | Category | | --- | --- | --- | --- | | [Guess the Rule: Logic Puzzles](https://appshunter.io/ios/app/guess-the-rule-logic-puzzles/id1550411766) | 4.7 (30) | Free | Games | | [Brain Smash](https://appshunter.io/ios/app/brain-smash/id888771025) | — | Free | Games | | [Neuroshima Convoy card game](https://appshunter.io/ios/app/neuroshima-convoy-card-game/id1527545755) | 3.6 (14) | $3.99 | Games | | [Bubble Burst™](https://appshunter.io/ios/app/bubble-burst/id532942792) | 4.6 (91) | Free | Games | | [LogicCity Jr](https://appshunter.io/ios/app/logiccity-jr/id936822232) | 4.6 (11) | $1.99 | Games | | [Match52](https://appshunter.io/ios/app/match52/id1539287663) | 5.0 (22) | Free | Games | ## More apps by Elitza Maneva - [FIFO & the Times Table Aliens](https://appshunter.io/ios/app/fifo-and-the-times-table-aliens/id1543399639) All apps by Elitza Maneva: https://appshunter.io/developer/1347885939 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*