To this day, Android users still are not able to use the Mobile companion app to access in-game features such as training your dog "Chop", or choosing custom license plates for your cars.
A few automated responses from Rockstar claiming the app is coming "soon" are what the disappointed fans received as answers. Many users on Rockstar's own comments claim they won't be playing GTA 5 or be purchasing anymore Rockstar published games.
Some users came up with a theory that Apple itself is stoping Rockstar from releasing the Android app due to the name itself. Although Rockstar has stated this is NOT the case, most still believe it is.
Unfortunately, there is no release date yet. I'm sure Rockstar will get this sorted out after they get the GTA:Online debacle fixed.