One By One: Mental Math

Name: One By One: Mental Math
Rating: 4.8 (77 reviews)
Author: Brice Brown

Ace SAT, Algebra & Calculus

Free · In‑App Purchases · Designed for iPad. Not verified for macOS.

77 Ratings
Age Rating

4+
Years
Category

Puzzle
Developer

Brice Brown
Language

EN
English
Size

66.8
MB

Dominate ACT, SAT, and your math class! Solve Arithmetic to Calculus in a retro math game. Sharpen your skills with live speed stats, the new Sandbox mode, and CRT themes One By One is a retro math study game built for middle and high school students looking to level up their mental math skills. Featuring randomly generated problems, the app lets you switch from basic arithmetic to advanced calculus. You can also target specific practice areas using the One By One Battles mode or the premium Sandbox mode. Key Features Retro Calculator Aesthetic: Enjoy a nostalgic UI designed with classic Unicode and ASCII art, complete with satisfying mechanical key clicks and atmospheric background music. Four Math Disciplines: Practice everything from basic arithmetic and high school algebra to trigonometric functions (complete with a built-in unit circle) and calculus derivatives. Leveling System: Progress all the way from Level 1 to 99, unlocking brand-new question tiers every ten levels. AI Battles & Training: Test your speed in targeted training modes or race against AI opponents to earn in-game rewards. Artifacts & Upgrades: Solve rare "Golden Problems" to collect 25 unique math artifacts featuring 9 distinct upgrades to shape your strategy. Leaderboards & Achievements: Compete across 5 specialized leaderboards, including a balance-based leaderboard, and uncover hidden achievements. Download One By One and start solving math faster than your teacher! Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Ratings & Reviews

4.8

out of 5

77 Ratings

Great math game, but I have two suggestions!
01/30/2023
Player_1909
Long story short, this is one of the best math games I have ever played. You wouldn’t think it would be fun; after all, the problems aren’t disguised at all. However, with the fact that there are “golden” problems that give you artifacts and that there’s a “money” counter that goes up as you solve, it always keeps you coming back for more. I also appreciate the “Battle” Mode. However, I have two suggestions: make the “average time taken on arithmetic/algebra/trig/differential problems” display a “rolling average,” which excludes earlier problems. For example, only consider the times of the last 250 problems or so for the average. Since the point of this app is to get faster and better, a rolling average makes sense since after solving enough problems, it won’t matter how fast or slow you are, your average won’t budge since there’s so much data. It would help measure improvement and trends, showing how far you’ve come instead of reminding you of the past. It would also help refine precision for the battle mode, making sure you’re always being challenged no matter how good you are since you first started. Also, I’m over halfway done with collecting all the artifacts, and it’s worrying me about what I’ll do once I’ve found them all. For me, a big part of the game is the constant waiting for a golden problem. So, instead of having to add more artifacts, why not allow for duplicates once you’ve found them all? These duplicates would show as a simple number in the bottom-left corner of the artifact tile, and every duplicate you get would “upgrade” the artifact, making it more powerful. The boost wouldn’t have to be too big, but it would keep the thrill of golden problems after getting all of the artifacts. (More artifacts would not go unappreciated though.) However, One By One is a great app for anyone looking for a fun and fast way to improve their math skills, and it has problems for all ages: for a five-year old practicing addition, a fourteen-year old brushing up on algebra, or for a high-school student studying for their Trig or differentials final.

Developer Response
Wow. Thank you for such a heartfelt review. I am glad you enjoy the app. I completely agree with changing the average to be more recent. Additionally I think having the artifact upgrades could add another level to the game without too much complexity. I am currently taking a pause of updates but once I get back into I'll definitely add these.
Great math game, but I have two suggestions!
01/30/2023
Player_1909

Long story short, this is one of the best math games I have ever played. You wouldn’t think it would be fun; after all, the problems aren’t disguised at all. However, with the fact that there are “golden” problems that give you artifacts and that there’s a “money” counter that goes up as you solve, it always keeps you coming back for more. I also appreciate the “Battle” Mode. However, I have two suggestions: make the “average time taken on arithmetic/algebra/trig/differential problems” display a “rolling average,” which excludes earlier problems. For example, only consider the times of the last 250 problems or so for the average. Since the point of this app is to get faster and better, a rolling average makes sense since after solving enough problems, it won’t matter how fast or slow you are, your average won’t budge since there’s so much data. It would help measure improvement and trends, showing how far you’ve come instead of reminding you of the past. It would also help refine precision for the battle mode, making sure you’re always being challenged no matter how good you are since you first started. Also, I’m over halfway done with collecting all the artifacts, and it’s worrying me about what I’ll do once I’ve found them all. For me, a big part of the game is the constant waiting for a golden problem. So, instead of having to add more artifacts, why not allow for duplicates once you’ve found them all? These duplicates would show as a simple number in the bottom-left corner of the artifact tile, and every duplicate you get would “upgrade” the artifact, making it more powerful. The boost wouldn’t have to be too big, but it would keep the thrill of golden problems after getting all of the artifacts. (More artifacts would not go unappreciated though.) However, One By One is a great app for anyone looking for a fun and fast way to improve their math skills, and it has problems for all ages: for a five-year old practicing addition, a fourteen-year old brushing up on algebra, or for a high-school student studying for their Trig or differentials final.
Developer Response 02/01/2023
Wow. Thank you for such a heartfelt review. I am glad you enjoy the app. I completely agree with changing the average to be more recent. Additionally I think having the artifact upgrades could add another level to the game without too much complexity. I am currently taking a pause of updates but once I get back into I'll definitely add these.
Almost Perfect
11/22/2023
AAFMOHEM
This is a wonderful app and great opportunity for practicing mental math. And this is why I care enough to make a bug report.Please fix calculus. Some of the answers require infinity, and this is not allowed in the answers. For example, I recently got the question: Given h(x) = 8/x find h’(0). The answer is -∞ as this is the limit from the left and right hand sides, but this is impossible to enter with the ‘Differential Departments’ keyboard. One possible stopgap solution would be to make the correct answers available if you pay for a skip (with in-game currency), this way we users can figure out what the game wants in such strange situations. Alternatively, you could take away the questions generating these issues, possibly by plugging all differentiation questions into the Wolfram engine to check the outcomes and then deleting the ones that don’t match. Of course, this won’t work if the questions are auto generated and not drawn from a bank —unless you run all possible questions (which would probably take a long time).
Almost Perfect
11/22/2023
AAFMOHEM

This is a wonderful app and great opportunity for practicing mental math. And this is why I care enough to make a bug report.Please fix calculus. Some of the answers require infinity, and this is not allowed in the answers. For example, I recently got the question: Given h(x) = 8/x find h’(0). The answer is -∞ as this is the limit from the left and right hand sides, but this is impossible to enter with the ‘Differential Departments’ keyboard. One possible stopgap solution would be to make the correct answers available if you pay for a skip (with in-game currency), this way we users can figure out what the game wants in such strange situations. Alternatively, you could take away the questions generating these issues, possibly by plugging all differentiation questions into the Wolfram engine to check the outcomes and then deleting the ones that don’t match. Of course, this won’t work if the questions are auto generated and not drawn from a bank —unless you run all possible questions (which would probably take a long time).
Wonderful math app!!
07/02/2023
Dalton Suede
My free time is so much more productive with this fun app! The way that the problem streaks are timed makes it exciting and the currency system feels rewarding. Using this app is just as fun as other puzzle games but instead of mindless puzzles, it helps you develop practical knowledge! The user interface is also really well done, stable, and easy to use. I reccomended this app to anyone trying to improve their quick math skills! The only gripe that I have is that there isn't an 'explanation' section in the app to refresh my memory on how to do some of these problems. But other than that the app is perfect for math lovers! You won't regret downloading it, especially if you love math! 😄

Developer Response
Thank you so much for the kind words! I’m glad to see that the focus on making the experience rewarding worked out. I do agree that having a little “manual” for tricks to do the mental math faster would definitely enrich the experience.
Wonderful math app!!
07/02/2023
Dalton Suede

My free time is so much more productive with this fun app! The way that the problem streaks are timed makes it exciting and the currency system feels rewarding. Using this app is just as fun as other puzzle games but instead of mindless puzzles, it helps you develop practical knowledge! The user interface is also really well done, stable, and easy to use. I reccomended this app to anyone trying to improve their quick math skills! The only gripe that I have is that there isn't an 'explanation' section in the app to refresh my memory on how to do some of these problems. But other than that the app is perfect for math lovers! You won't regret downloading it, especially if you love math! 😄
Developer Response 08/05/2023
Thank you so much for the kind words! I’m glad to see that the focus on making the experience rewarding worked out. I do agree that having a little “manual” for tricks to do the mental math faster would definitely enrich the experience.
Love it, want more!
10/22/2023
Jawwastar
I’ve been having a lot of fun with the app! The derivative and trig section is great practice to knock the rust off my calc now that I’m back in complex analysis. I’d love to see more sections added such as integrals, combinatorics, some kind of series stuff, maybe even some set theory unions and intersections type stuff! I would pay for some extra packs of the sorts! Thanks!

Developer Response
Wow thank you for the amazing review! It is awesome to see that the app is appealing even for such a high level of math! Those modes would be great to see in the app one day.
Love it, want more!
10/22/2023
Jawwastar

I’ve been having a lot of fun with the app! The derivative and trig section is great practice to knock the rust off my calc now that I’m back in complex analysis. I’d love to see more sections added such as integrals, combinatorics, some kind of series stuff, maybe even some set theory unions and intersections type stuff! I would pay for some extra packs of the sorts! Thanks!
Developer Response 10/27/2023
Wow thank you for the amazing review! It is awesome to see that the app is appealing even for such a high level of math! Those modes would be great to see in the app one day.

Massive Retro Overhaul & Supporter Update! We’ve completely rebuilt One By One from the ground up for a smoother, more tactile math experience. Here is what’s new in this version: UI & Aesthetic Overhaul Tactile Mechanical Keys: Flat sprites are out. Enjoy a responsive native layout with traveling keycaps, haptic clicks, and zero-blur drop shadows. Dynamic LCD Screen: A true-to-life LCD print head now amends text character-by-character as you solve instead of just refreshing. Polished ASCII Graphics: Redesigned unit circles, level badges, and progress bars match the new physical grid perfectly. New Supporter License & Themes Premium Themes: Supporters can now swap the classic cream design for new terminal themes: Phosphor (Green CRT), Amber (Gas-plasma), and Papertape (Teletype). Cash Multiplier: The Supporter License also grants a permanent 1.25x practice cash bonus. Sandbox Mode & Advanced Stats Sandbox Mode: Experiment and practice specific problem types at your own pace without pressure. Live Balance Graph: Track your recent earnings with a dynamic ASCII plot covering your last 30 minutes of gameplay. Speed Tracking: Watch your mental math improve with real-time average seconds-to-solve tracking. Math Engine Improvements & Bug Fixes Crash-Proof Parsing: The answer checker now safely handles malformed inputs and typos without throwing errors. Calculus Fixes: The derivative generator is smarter and will no longer ask for derivatives at undefined or impossible points. Algebra & Trig Fixes: Restored previously "hidden" equation shapes (like x-a=b) to your runs, and fixed the mathematical ranges for inverse cot problems.

Version 1.9.0 Sep 1

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Accessibility

Information

Seller: Brice Brown
Size: 66.8 MB
Category: Puzzle
Compatibility: Requires iOS 15.0 or later.

iPhone
Requires iOS 15.0 or later.

iPad
Requires iPadOS 15.0 or later.

iPod touch
Requires iOS 15.0 or later.

Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.

Apple Vision
Requires visionOS 1.0 or later.
Languages: English
Age Rating: 4+

4+

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In-App Purchases: Yes

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Monthly Support $1.99

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