Comparison

Even or odd Mental calculation vs 2357!

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

Head to head
About

Even or odd Mental calculation

Test your mental math skills by quickly determining if the result of an on-screen operation is even or odd. Earn more points for faster answers and challenge friends to see who has the quickest mind. The difficulty increases as you progress.

Highlights
  • Timed mental calculation challenges
  • Score tracking for personal bests
  • Speed-based scoring system
  • Increasing difficulty levels
  • Multiplayer comparison
Features
Read full description

Solve the calculation and choose: is the answer even or odd? Par o Impar combines addition, subtraction and multiplication with short sessions and two large answer buttons. Practise at your own pace or test your speed across five modes: - Classic: answer before time runs out and try to beat your record. - Sprint 60: get as many answers right as you can in one minute. Each mistake costs three seconds. - Daily Challenge: 20 calculations each day, with one official attempt and unlimited practice afterwards. - Training: choose addition, subtraction, multiplication or a mix. Play without a timer and see an explanation after each answer. - Challenge Route: complete 30 levels involving calculations, accuracy and memory, and earn medals. A short tutorial explains the controls. Pause your game, adjust sound and vibration, and check your records. Progress is saved on this device and all game modes work offline. The game interface is in Spanish. The app contains advertising. If you previously bought ad removal on iOS, you can restore it from Settings (Ajustes).

About

2357!

Engage in a fast-paced division battle game where you destroy target numbers using prime factor combinations within a 60-second time limit. Improve your calculating skills and compete globally in this brain-training puzzle.

Highlights
  • 60-second division battles
  • Destroy target numbers with prime factors
  • Score multipliers for simultaneous throws
  • Global ranking competition
  • Brain training and calculation skill improvement
  • Intuitive and easy one-hand play
Features
Read full description

◇◇◇ 60-seconds division battle game!!◇◇◇ What you should do is to destroy the division ball !! It's a simple game but profound and makes you smarter!! With the combinations which is composed of primes(2,3,5,7,11,13,17,19),how many divisors can you compute!? Be popular with who is fond of puzzle, crossword, sudoku, prime factorization etc. brain training games!! ◆ SIMPLE RULE ・Time limit: 60 seconds ・Throw the divison balls to destroy the target ball !! ・Destroy the target ball with several divisions ball in a time, get more hight score!! ・The number of target ball will become larger!! ・Simply put, it's Division. ・Or you can say it's Prime Factorization. ◆Easy to play ・Enjoy brief game in one-hand!! ◇◇◇◇◇◇◇◇◇◇◇◇◇◇◇ ◆ Ex.1 ・When 「6」is the number of target ball ① Throw the number 「2」down ② Throw the number 「3」down ③ Get 6 points!! ◆ Ex. 2 ・When 「6」is the number of target ball ① Throw the numbers「2」and「3」at the same time ② 6x2=12, Get 12 points!! ◆ Ex. 3 ・When 「30」is the number of target ball ①Throw the numbers「2」,「3」and「5」at the same time ②2x3x5=30, and Get 90 points!! ◆ Tips to get higher score ・As you clear, the number of target ball will become larger!! ・Take Ex.2 for example, throw 2 numbers at the same time to get double score!! ・throw 4 numbers at the same time to get quadruple score!! ・Play more and remind the combination!! ・Try hard to avoid all mistakes!! ・How about challenge an astronomical number!? ◆ Win the Global Ranking ・Battle to other users in GameCenter in the world!! ・To be the champion! ◇◇◇◇◇◇◇◇◇◇◇◇◇◇◇ ◆ Prime Factorization means? ・Simply put, divide the target number to be 「1」finally!! ◆ It may looks simple but profound ・Even the schoolchild can play the game ◆ Brain training by intuition ・Everyone can enjoy it!! ・Also good brain training to adult!! ・Play when you're free!! ・Train the calculating skill more faster!! ・Activate your brain!! ◆Someone who will definitely like it ・Solve Prime Factorization in speed!! ・Avoid dementia and Alzheimer's disease!! ・Popular!! Of course it's for free!! ・A good way to communicate with children and parents!! ・Different from other puzzle games!! ・Play it anytime!! ・Show your calculating skill!! ◆CREDIT HANAUTA INC. Ueki Mitsuda Nojima Fukutomi

Screenshots

Even or odd Mental calculation4 screens
2357!4 screens

Verdict

The call

The clearest difference is in-app purchases: 2357! at none against Even or odd Mental calculation's 1. 2357! also leads on ads (none vs shown) and update cadence (every 2 weeks vs every 23 months). Even or odd Mental calculation's advantage is review sentiment (100% vs 89%). On price 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. Even or odd Mental calculation sells 1 one-off in-app purchase. 2357! asks for nothing beyond the download.

UpkeepUpdate frequency

Even or odd Mental calculation ships an update every 23 months, 2357! every 2 weeks. The most recent releases landed on November 1, 2026 and November 2, 2026 respectively.

Scorecard6 real differences · 4 level
Even or odd Mental calculation versus 2357!: the parameters behind the verdict, then further details
ParameterEven or odd Mental calculation2357!
PriceFreeFree
Rating—4.0 (3 ratings) — better
Positive reviews100.0% of reviews — better89.5% of reviews
Number of ratings—3 — better
Update frequencyEvery 23 monthsEvery 2 weeks — better
AdsYesNo — better
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.07.0 — better
Further details — not scored
Size68 MB156 MB
Age rating4+4+
DeveloperIker VazquezHANAUTA INC.

Customer experience

Even or odd Mental calculation

Written reviews5 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

2357!

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews19 reviews
Positive89.5%
Neutral10.5%
Negative0.0%

In-app purchases

1 purchases

Even or odd Mental calculation

One-time1
  • Full version upgrade$0.99
None

2357!

No in-app purchases

Questions

Is Even or odd Mental calculation free?
Even or odd Mental calculation is free to download, with in-app purchases available.
Is 2357! free?
2357! is free to download, with no in-app purchases.
Do Even or odd Mental calculation or 2357! have ads?
Even or odd Mental calculation shows ads; 2357! does not.
Which is updated more often, Even or odd Mental calculation or 2357!?
Even or odd Mental calculation ships an update every 23 months, and 2357! every 2 weeks. Most recently, Even or odd Mental calculation was updated on November 1, 2026 and 2357! on November 2, 2026.

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