[theBobMcCormick]

That's a strawman. Android users don't need to keep track of what's running and what should be killed at all. The OS keeps track of it all.

Android actually has a pretty damn clever model where normally Activities are killed whenever they're not visible (similar to the iPhone model). However, and application can register service processes that run in the background to do things like play music, check for updates (email, IM, etc).

The difference between the Android and the iPhone model is actually pretty small. The main difference is that on the iPhone, only certain Apple provided apps can do things like play music in the background, get background notifications, etc. In Android, third party applications can also be written to do those things.

But in the most common case of apps that don't do things in the background, the application lifecycle of iPhone apps and Android apps is actually quite similar.