I believe 2.2 will give you Android Auto and Apple Careplay support. Note that your truck must have the upgraded USB hub installed for this to work so it isn't just a software fix.
Andy said most of it. 2.X gives you Android Auto and Car Play. If you have a Late 2016 or 2017 most likely you do not need an updated Hub. The Newer hub is only needed for Car Play, Android Auto works with any version of the hub that comes with a Sync 3 equipped vehicle.
2.X also had several improvements in the voice prompts, it has less delay, and seems to be more concise in it's response.