Here are some screenshots of AscBinHex running on a range of devices.
This is on an iPod (iOS 6.1)
This is on an iPhone 4s (iOS 8).
The default view. ASCII data is being entered using the rotating selection wheels.
This is on an iPhone 6 (iOS 8).
You can see the binary input keyboard.
This is on an iPhone 6 (iOS 8).
You can see the hexadecimal input keyboard.