Why do you need to clear memory? There should be plenty of it for apps, and it seems unlikely for a person to be regularily using the 20 or 30 apps (or more it seems like, I only have a few) it would take to run low on space. I'd opt for deleting apps off your phone that you don't use before trying to get rid of OS stuff.
That being said, I always go in when I get a new OS and drop all the stuff I don't need like extra languages, Documents to Go, all the games, and even things like TTY and password keeper.
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