There is NO Tivo app for android. TivotoGo is part of a PC program (Tivo desktop, I think) that you download from Tivo.com, and it connects over your network to transfer files off of your Tivo. You can use TivotoGo to transfer your shows to other devices like a laptop or phone, in a file format they can use. Because the Tivo box itself uses a proprietary format (I have no idea why they didn't use a standard format).
Once you have the file on your phone, you play it with a video player app like Meridian.
I have seen posts about ripping DVDs to put on the phone, but this is the first way I have found to put TV shows on the phone.