Ashley The results of the test so far:
With WebGL off: Still crashed at level load.
Webview and Webview+: Still crashed at same point.
Canvas+: Only version that didn't crash, performance as smooth as on desktop. The only drawback is that the screen is shrunk and takes up only the lower left quarter of the screen. Touch buttons are still mapped to where they should be on screen despite shrunken image.
Perhaps the reason Canvas+ has 1/5th the performance of Webview is due to being a more stable for certain games like mine?
PhoneGap: Behaved similarly to the webview version of Cocoon, in that it crashed at the same spot, right after the main menu, when the level is loading after hitting play. PG has waaayyy faster load time than Cocoon though. While Cocoon took 10 to 15 seconds, PG went through the load bar in 3 to 5 seconds.
No Browser plugin: Still crashed on webview/+ Cocoon and PG.
So I can only assume that something in the playable level of the game is responsible for the crashes. I can't think of any culprit other than that layout has the most assets.
Everything else in the game works on all versions, going through the info/tutorial pages does not cause crashing, leaving it on the menu for a minute doesn't result in crashing.
So it definitely is something in the level. In conclusion, the only solution would be to make a new empty level from scratch, and include minimal stuff in it.