Can I introduce two Hio Contacts? How?

Yes, and this is a feature of the Hio Premium membership!. Select the first person you want to introduce by going to your People tab (bottom left tab), and from their profile, tap the (...) button at top right. This will display a list of options. Select the option "Introduce Hio Contacts." Then select the person you want to introduce your friend to and advance. Customize the introduction with a few comments and send.