Write to file in Documents directory

fileout.txt

// Get documents directory
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];

// File
NSString *fileName = [NSString stringWithFormat:@"%@/textfile.txt", documentsDirectory];

// Write to file
NSString *string = @"Example";
[string writeToFile:fileName 
                atomically:NO 
                encoding:NSStringEncodingConversionAllowLossy 
                error:nil];