I have an iPhone 3 and it has suddenly started constantly running everything I open or use in the background. It spontaneously started doing this today and is sucking the battery life. For example, when I've made or received a phone call, or I set the alarm or go into contacts, I then find if I double tap the home button it's running all of these in the background. I know how to close them but how do I stop it automatically constantly running them in the background? Annoyed & confused!