I am using the latest version of cocos2d-x with my game,and found that android devices with gles version below 2.0 not supported.
I have a suggestion that the framework support the gles2.0 and gles1.x simultaneously,
that is when the framework detects that the device with a gles of version 2.0, it use the shaders for rending while with the version 1.x,
it use the plain old way.
so, the game built with cocos2d can run on more devices while on the newest devices it can also achieve a dramatic performance.