I think Sanjay's answer was almost there but i used it this way
NSArray *myArray = [[NSArray alloc] initWithObjects:@"Hello",@"World", nil];
NSString *greeting = [myArray componentsJoinedByString:@" "];
NSLog(@"%@",greeting);
Output :
2015-01-25 08:47:14.830 StringTest[11639:394302] Hello World
As Sanjay had hinted - I used method componentsJoinedByString from NSArray that does joining and gives you back NSString
BTW NSString has reverse method componentsSeparatedByString that does the splitting and gives you NSArray back .