It sometimes happened that some app has a discount price (christmas - black friday), it is possible to check the price trend during the past?
Mayve the bookmarked app
It could be useful to decide if buy an app that is not strictly necessary
Android Enthusiasts Stack Exchange is a question and answer site for enthusiasts and power users of the Android operating system. It only takes a minute to sign up.Sign up to join this community
App history (source: AppBrain; click image for larger variant)
As the screenshot shows, you get a price history along with the changelog (right part) if the app was paid – and you also get a rating history (left part).