Big framerate difference on X86 and ARM

Hi there my game (as pictured) is all about 200 color animated bricks (all same) and some particle system background. its on Android platform.

the problem is : when previewing game on my PC, the framrate is above 140 fps. its ok. when previewing game on my PC and i check "maximize on play", the framerate drops to under 70 all the time. its low. but it has no lag and it's still playable. when i play it on my ASUS memopad8 tablet (intel 3745 X86 chipset) the game is as smooth as silk. no lag at all. (720p resolution). when I play it on an HTC one E8 (Snapdragon 801,1080p res) and Asus Zenphone Laser (SnapDragon 615,720p res) framerate drops heavily. its unplayable. and that's the problem.

What I've Done and got no change : Disabled All sprites mipmap Generation, texture Compression. no luck. Disabled SSAA Script on Camera. no luck. disabled / enabled all options under "Optimization" in Player Settings. still nothing. Changed Image Compression method in bulid menu to adreno/ no override/ default ETC. no luck.

the Environment : 1) all sprites (2d and UI) are 2048 Compressed and MipMap Generation is enabled on them 2) a SSAA Anti aliasing script is attached to camera 3) my Android SDK is as shown on the second image 4) windows 10, an old ATI 4850 VGA, unity 5.1