How to display hexadecimal bytes using NSLog

If you want a hex sequence:

NSMutableString *hex = [NSMutableString stringWithCapacity:[devToken length]];
for (int i=0; i < [devToken length]; i++) {
  [hex appendFormat:@"%02x", [devToken bytes][i]];
}

Assuming that devToken is of type NSData * (from the bytes call), you can use the description method on NSData to get a string containing the hexadecimal representation of the data's bytes. See the NSData class reference.

NSLog(@"bytes in hex: %@", [devToken description]);