I believe that guildsoftware just spent several, several months optimizing android and are now looking to improve graphics/release on iPhone. I'm sure they'll do more optimizing when they have time though.

I don't believe this game was ever intended to be played solely on the phone, instead played primarily on PC, then use android/iOS as an "away from PC" alternative.

I spend more time playing the game on my phone, with a few exceptions. A phone in bed is just so much more comfortable than a laptop. The exceptions are during events, and while working on mission design (although I do some of my playtesting on a phone, and the mission editor works just fine on a phone, too).

You've got to remember this was a PC game first, and some of the scenes are a bit much for a mobile CPU/GPU to handle.

Try turning down some of the detail and texture resolution options under Video and Graphics. I'm able to play most things except for the biggest border skirmish missions on my Motorola Photon Q which isn't anywhere near as good as your Xperia M2.

As far as optimization goes, they've done that for the Qualcomm Snapdragon chips that our phones both use; including, but not limited to: a custom splash screen! :P