Problems with browser compatibility

Hi, my game does not run as espected on some browser, it runs perfectly fine on desktop browsers though.

One of my sponsors which I sold a license to told me that the game does not show graphics as they should.

This is what the game looks like with iPhone 4s:

The grid should not appear, I don't know where that grid comes from.

Also, on galaxy s2 and s3, when I change tabs on the browser and come back to the game, the game freezes.

I only have a galaxy s2 to test, the other devices where used by my client.

Any idea of how can I start to solve this problem?, what should I find out first? what do I need to learn?. Please help since I am not experienced in mobile browsers, any hint is appreaciated, thanks.

I still need help with this, any hints?, any ideas?, where could I learn the necesary things in order to find out what is going on?,

Thanks.

This is weird, at first I thought it could be seams, but it does not seems to be that.

Which object is used as the grass?

(Also did you tried in the latest stable?)

I didn't try the latest stable release, but does it solve any problems regarding this type of problem? I checked the change list and I didn't read anything like it.

The objects used are tilemaps and tiled background.

Thanks a lot for the reply.