Let me start by asking a simple question: currently, what is the quickest way to switch between apps on Android?
If you have already opened the app, then simply pressing and holding the home button on your phone will show you it on a list of recent apps. (If your phone came with ICS, it may even have a dedicated button just for this.) But every time you restart your phone, the recent apps list is emptied – and sometimes, of course, you’ll want to switch to an app that you haven’t opened recently. In either case, you’ll have to open up the app drawer and scroll through the multitude of apps residing in there to find the one you want.
SwipePad: Hyperspace Jump is a much better solution. It allows you to “launch anything from within any app”, as the developers, Calcium Ion, put it. But don’t be fooled; this app’s functionality exceeds just switching between applications…