Try them on ICS too.
http://www.techrepublic.com/blog/five-apps/five-apps-to-help-you-clean-up-your-android-device/1252
I find this issue to be more common.
http://stackoverflow.com/questions/8870715/android-cleaning-up-memory-on-app-destroy
My fix for that is to reboot once in awhile.
Bob
I'm using Nexus S and overtime I realized that there's a lot of garbage/leftovers in it from the deleted apps and stuff like that. Is there any app like CCleaner for Windows, that can "clean" the phone from this stuff?

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