Detect the type of iPhone Device independent from iOS version

devicetype.m

// Detect the type of iPhone Device independent from iOS version
    CGSize size = [UIScreen mainScreen].bounds.size;
    CGFloat r = size.width > size.height ? size.width / size.height : size.height / size.width;
    if (r < 1.5) {
        // iPad
    } else if (r == 1.5) {
        // iPhone 4
    } else if (r > 1.5) {
        // iPhone 5/6/6+
    }