The Samsung Galaxy S3 comes with a massive 4.8 screen & the latest Android OS. It has good build quality, comes in a nice blue colour or white.
The Galaxy S II by Samsung features a 4.3″ screen and runs the Android operating system. It is the successor the the Galaxy S which was launched in March 2010. The Galaxy S II was launched in February 2011.
The Galaxy Ace GT-S5830 by Samsung is a smart phone running the Android operating system. It has a 3.5″ screen and 5 Mega Pixel Camera.