hi Friends I was looking for Screen Size of background but did not get it here so i found it some where else so posting here it might help someone else also
ldpi mdpi hdpi xhdpi xxhdpi xxxhdpi
Launcher And Home 36*36 48*48 72*72 96*96 144*144 192*192
Toolbar And Tab 24*24 32*32 48*48 64*64 96*96 128*128
Notification 18*18 24*24 36*36 48*48 72*72 96*96
Background 240*320 320*480 480*800 768*1280 1080 *1920 1440*2560