How do I check if the useragent is an ipad or iphone?

UPDATE on 17-07-2020: it looks like Apple removed the word iPad and now use Macintosh instead

UPDATE:
Since the iPad user agent contains the word iPhone as @Rob Hruska mentioned:

Mozilla/5.0(iPad; U; CPU iPhone OS 3_2 like Mac OS X; en-us)
AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B314
Safari/531.21.10

and iPhone user agent is something like this:

Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0 like Mac OS X; en-us)
AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A293
Safari/6531.22.7

it would be correct to check for the word iPhone; or iPad; to identify the device:

var userAgent = HttpContext.Current.Request.UserAgent.ToLower();
if (userAgent.Contains("iphone;"))
{
    // iPhone
}
else if (userAgent.Contains("ipad;") || userAgent.Contains("macintosh;"))
{
    // iPad
}
else
{
    // Think Different ;)
}