Many apps for IOS offer paid subscription services. In the Apple Appstore there are also many applications which come with subscriptions and recurring payments. Examples are utility apps like Evernote, music services like iTunes Match, educational apps like ISkills or self improvement apps like Headspace. There are more and more such apps in all application categories in the iPhone app store.
Usually it is very easy to sign up for the service and trigger recurring, monthly payments. Many users just forget about these apps and keep paying for a long time without actually using the service any longer.
Getting rid of unwanted subscriptions can be a hassle. In some apps you can simply deactivate the subscription from within the app.
In many apps though unsubscribing has been made - deliberately or not - difficult. You need to find the somewhat hidden section in the settings of the iTunes (on PC or Mac) in order to manage these subscriptions.
This video shows how to get an overview of all active and previous subscriptions and to cancel and unsubscribe app subscriptions you don't need any longer.
