How to back up Glow data on iPhone???

Sally • 24 year old feminist and humanist.
I have a new laptop and need to sync my iPhone with it, but I'm scared to lose all my data from the app!! 
I read somewhere to create an iCloud back up but this app doesn't appear on the list of apps which are to be backed up :/
Itunes and apple things are so confusing :(
Any help would be greatly appreciated!!