When you try to log into the app and a message displays telling you to allow Odd Socks to have access to your Facebook account.
You can do this by going to your Phones 'Settings' and scroll down to the Facebook option, it'll be grouped with your other social media apps.
Once your in your Facebook settings you will see a few apps that you've already allowed access to your Facebook account, Odd Socks will be under these and will be enabled. Once you've enabled Odd socks load the app back up and you'll be able to play.
To enable Odd socks access slide the bar across.