Learn Backbone.js Offline PRO is not free (it costs 0.99), however it doesn't contain in-app purchases or subscriptions.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
The price of Learn Backbone.js Offline PRO is 0.99.
To get estimated revenue of Learn Backbone.js Offline PRO app and other AppStore insights you can sign up to AppTail Mobile Analytics Platform.