How to restore an app to recently used app bar after deleting it from bar?

Question

I frequently have to kill an app (GPS Drive) in order to get it to work properly alongside another app (HiDef Radio). Reason being: When I use the two apps at the same time, the HiDef Radio frequently renders the live voice guidance on GPS Drive inoperable. A customer support representative for GPS Drive advised me to kill GPS Drive, using the recently used apps bar, and re-open it when this happens. (The representative also said that they just submitted a new version of GPS Drive to Apple, which should hopefully fix this problem, but in the meantime, I'm stuck not being able to listen to the radio and use live voice guidance at the same time.)
To kill GPS Drive, I followed the instructions in the iPhone 4.1 manual:
"Remove an app from the recents list: Touch and hold the app icon until it begins to jiggle, then tap [the red minus]."
The manual then states, "The app is added to recent apps again the next time you open it."
Problem is, contrary to what the manual says, GPS Drive is not added to recent apps again the next time I open it. And since it's not added back to the recent apps bar, I can't kill it next time I have this conflict with HiDef Radio. So the problem remains.
Is this—the fact that the app is not added to recent apps again the next time I open it—some sort of bug? (And, if so, is the bug Apple's, or GPS Drive's?) Or am I missing something? (And, if so, how do I make the app re-appear in the recently used apps bar after removing it from said bar?)
If anyone is wondering how I know that removing an app from the recently used apps bar kills it, see this, from http://support.apple.com/kb/HT4211 :
"If you experience issues with applications that use multitasking, try these steps to troubleshoot:
"1. Check the App Store to verify the application supports multitasking. You can also check the developer's webpage.
"2. Close the application and reopen it:
" 1. Double-click the Home button to load recently used apps:
" 2. Select the application by tapping and holding on the application until the red minus appears:
" 3. Tap the red minus to quit the application. This also removes an application from recently used apps."
Thanks in advance for your help.

Answer 1

I just discovered the answer to my question. Apparently, when you're in an app, that app does not appear in the recently used apps bar. This is logical in one sense: You can't switch to an app that you're already in. However, in another sense, it is illogical: In most operating systems, when you want to kill an app, you can kill the app without exiting the app (which is necessary in cases in which a freeze prevents you from exiting the app) by using a keystroke or directly entering a task manager. Given that the recently used apps bar serves two purposes—fast app switching and killing problematic apps—what makes sense for one purpose doesn't make sense for the other purpose. Anyway, the moral of the story is this: If you want to kill an app using iOS 4, you have to exit it first. Problem solved.