Comparison

Primality vs Prime Factors +Calc

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

Head to head
About

Primality

This app determines if a given integer is prime or provides its prime factors. It also calculates the ordinal position of prime numbers found, up to a certain limit.

Highlights
  • Primality testing
  • Prime factorization
  • Prime ordinality calculation
  • Large integer support (up to 999,999,999,999)
  • Clean and simple interface
Features
Read full description

The Primality App has a clean and simple, yet powerful, function: Given any integer, the app determines either that the given integer is prime or else it provides all prime factors of that integer. Very clean, very simple, focussed. The app operates in the range of 0 - 999,999,999,999. A popular feature of the app is its ability to determine the prime ordinality of each prime found, such as observing that 97 if the 25th prime. (However, this particular feature is available only up to the 100,000th prime, which is 1,299,709.) Requires iOS 13 or higher.

About

Prime Factors +Calc

Features
Read full description

A simple and easy-to-use app for prime factorization and divisors display. It also features a calculator that supports fractions.

Screenshots

Primality2 screens
Prime Factors +Calc4 screens

Verdict

The call

The clearest difference is update cadence: Prime Factors +Calc at weekly against Primality's every 2 months. Primality's advantage is iOS requirement (13.2 vs 16.0). 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.

UpkeepUpdate frequency

Primality ships an update every 2 months, Prime Factors +Calc weekly. Both last shipped on October 24, 2026.

Scorecard2 real differences · 8 level
Primality versus Prime Factors +Calc: the parameters behind the verdict, then further details
ParameterPrimalityPrime Factors +Calc
PriceFreeFree
Rating4.9 (26 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings26 — better—
Update frequencyEvery 2 monthsWeekly — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPodiPhone, iPad, Mac — better
Requires iOS13.2 — better16.0
Further details — not scored
Size1 MB1 MB
Age rating4+4+
DeveloperBruce SchechterKazuaki Oshiba

In-app purchases

None

Primality

No in-app purchases

None

Prime Factors +Calc

No in-app purchases

Questions

Is Primality free?
Primality is free to download, with no in-app purchases.
Is Prime Factors +Calc free?
Prime Factors +Calc is free to download, with no in-app purchases.
Do Primality or Prime Factors +Calc have ads?
Neither Primality nor Prime Factors +Calc shows ads.
Which is updated more often, Primality or Prime Factors +Calc?
Primality ships an update every 2 months, and Prime Factors +Calc weekly. Most recently, Primality was updated on October 24, 2026 and Prime Factors +Calc on October 24, 2026.

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