You both said you're running version 2 of android - how old are your devices? Performance gains have been dramatic in the mobile area, so even having a device that's even a year and a half old can make a big difference. Also, as I've heard android 4 got a significant html5 speed boost as well.
Can you post your games? Did you at any point add physics to your project, even if you removed it later? You can try making a backup then deleting code and sprites bit by bit to find out what's hitting the frame rate. You can also try ranma's performance tips in the tutorial section (use the search in the tutorial section for performance).