There are several models of Trax: Trax T12 (Kickstarter), Trax T13, Trax T14 and Trax Play.
In general Trax Play has improved hardware components (in comparison to a T13 Trax) and it has a more secure USB door as well as a more flexible power button.
We are also working on a new firmware that will allow to manually change how often the tracker updates its position from inside the app.
Besides there is a difference in price and dataplans, as Trax Play is sold separately from the dataplan.
You can see all the different options in our webshop.