I successfully made a little app with 3 trackables and 3 objects in Unity. My Android device is Samsung SII.
It works fine with a few minor problems and one bigger: I experience the application very slow with 3 objects displayed. All objects are low poly. What is weird that I see the rendering of objects fast I mean they move with trackable very fine, but the camera reaction time is slowed down significantly. I see my hand with great lag :)
My app would be a skeleton of a later game, but this big reaction time is very annoying and renders the game not funny to play with.
Any help is greatly appreciated. Im not sure it is just my hardware or I miss sth when made the app in Unity.