An anti-answer: Use as few apps as possible, and when you do download ones, make sure to go into Settings -> Manage Applications and move them to the SD card if they didn't automatically install there.
Don't know how the SGS2 is in this regard, but my Nexus S absolutely chugs if I'm not careful to keep main memory as free as possible.
Don't know how the SGS2 is in this regard, but my Nexus S absolutely chugs if I'm not careful to keep main memory as free as possible.