OnyxBits has released a new Android IF interpreter called TextFiction. While not quite as full-featured as iFrotz on iOS, it looks to do a good job with classic Infocom games using Z3, Z5, Z8 files as well as more modern (and larger) ZBlorb games created with Inform. It also provides a cool "text message" type of user interface that looks pretty cool.
You can download the app from Google Play or get the source code directly from GitHub. So if you've got some old Infocom games lying around, or want to investigate modern games written in Inform, TextFiction looks like a good way to bring the games onto Android. There are plenty of free Interactive Fiction games available on IFDB.
I don't have any Android devices personally, so I've not been able to test it out. If you're an Android user, let me know how you like TextFiction by posting to the comments below.