Joe, that information is not correct. I use a fourth generation nano with my Spyder and it works perfectly . I can control selection of playlists, skip songs, etc. from the handlebar controls. I also have a newer iPod with the new lightning plug. As Deeprzymus just pointed out above, that also works perfectly if you use the 30 pin to lightning adapter that Apple sells. So bottom line, just about any iPod will work with the Spyder, with the possible exception of some of the very early models that may not charge properly.
Also worth mentioning is that if you are going to use the 30 pin to lightning adapter , use the one that Apple makes. Some of the cheaper knockoffs that you find on eBay and Amazon may not work.