So I found this tutorial ( https://www.scirra.com/tutorials/9432/h ... ova/page-1 ) Note that this does not use Intel XDK.
It shows how to build crosswalk apks on your local system which you can directly test on your phone. It works and I built a project which I tested on my phone which runs on Android 5.1.1 . The first couple of builds the game ran smoothly, definitely near 60fps, as it was same as when tested on my laptop. Then I started forking around to get Admob and appodeal working, and built again. I got the ads to work, but the game ran much slower. I thought it must be the appodeal or admob plugins as I haven't changed anything in the game itself, so I removed them. But the game remained slow. So I completely deleted everything and redid the tutorial. But again, the game was slow.
But then I realized that the game was NOT inconsistent in its fps. It was not lagging or stuttering in input or sprite movements, it was just at a steady low fps. So I rebuilt with an fps counter, and found that the fps was at a steady 30 fps. Throughout the game it just stayed at 30fps no matter if object count increased or decreased. What's even stranger is that when I build the project in portrait mode and run the game, it runs at a steady 40fps!
This is so weird. Does some setting limit fps in crosswalk? I'm certain I can get ~60fps as it was in the first couple of builds. I don't know how to proceed. Can anyone give an idea on what could be the problem?