Apps like this are a gift and a curse. For everyone with a compatible device, you get to unlock a lot of extra content in a console game and prepare some aspects of the game before it even launches. For those without a compatible device, it means you get left behind. What is not clear is how much of the car you design in the app will be locked behind pay walls once you attempt to import it.
I am not sure if this app will have any real value once the game is available, unless it is somehow easier than using the game. It is not the first time EA has created a gap in their player base with content coming from external sources. The risk that unlocking cars may become exclusive to a mobile app also causes a lot of concern.
If there is any chance you might buy the full game, then this is probably something you should at least download. Whether or not you make use of all the features, you might obtain some added content.
https://www.youtube.com/watch?v=mNYfeHfxsGE
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