Very solid.
Great value - I use this app at least once a week.
Yes, Spine is completely free and it doesn't have any in-app purchases or subscriptions.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
Spine is free.
To get estimated revenue of Spine app and other AppStore insights you can sign up to AppTail Mobile Analytics Platform.
Great value - I use this app at least once a week.
Super app. Very helpful.
Really good - only the good stuff. Saves a lot of time on PubMed...