(Square Root, GCD, Prime Numbers 3 in 1)
This app simplifies square roots and cube roots; finds the GCD(HCF) & LCM of 2 to 9 numbers in any order; checks if a number is prime or not and counts the number of prime numbers between 2 given numbers.
1) Swipe upwards to enter/exit GCD(HCF) & LCM screen.
2) Double tap the GCD(HCF) & LCM screen to clear all slots and results.
3) Swipe again to enter prime number screen.
Tested on iPhone 4s, 5s, 6, 6 Plus and iPad Mini 2 under iOS 9.3.4
How to fix Game Center problem in iOS 9:
iPhone Settings > Game Center > Your Apple ID and Tap Sign Out then Sign back in.