If you've already grabbed a season pass for $19.99, you'll be able to download the title on PC, Mac or iPad for free. If you skipped the subscription but purchased the first episode, you can upgrade to the season pass for another $9.99. If you didn't do that, you probably should go read a news article that's more relevant to your interests. Hey, here's some Wappy Dog screenshots! Go chew on those for a while.
Update: A Telltale representative informed us that the Hector season pass only just became available with the release of the series' second installment -- making it highly unlikely that any of you actually have it yet. Also, the $19.99 fee does not cover the iPad version of the game; those episodes have to be purchased piecemeal on the App Store for $6.99 a pop. We apologize for the confusion.