Q: How can I get off of a service and cancel it

You can't void a purchase. There are no refunds in the App Store, iTunes or the iBooks Store. You can ask and you may be granted an exception, but you are not entitled to one.

If you want to try to get a refund, contact iTunes Store Support.

https://www.apple.com/emea/support/itunes/contact.html

That's different. Hold down on the app icon until it wiggles or shakes on the screen. Then tap the X in the upper left corner of the icon in order to delete it. Then tap the home button when you're done and the app icons will stop shaking.

You're welcome.