It has a different layout, that I find easier to use, but also more stable.
The main difference for things that are currently in the new app: You can spin the log-in wheel in the app, read articles/get Sparkpoints for reading articles and view SparkPoints/Fitness Minutes Leaderboards.
But also, the new app continues to get updated, whereas the old free app will not be updated at all.
Hope that helps,
"You may have a fresh start any moment you choose, for this thing that we call "failure" is not the falling down but the staying down." Mary Pickford
"No matter how slow you go, you are still lapping everybody on the couch."