Samsung Nexus S (Sprint, T-Mobile, AT&T)

Almost from the moment Google released its Android operating system, carriers and manufacturers began cooking up ways to add their own identifying touches to the free, open operating system. Smartphones that feature the "pure" Android experience are relatively few and far between compared with the volume of phones decked out with custom interfaces, but we rustled up some for you here.

The Samsung Nexus S (originally for Sprint, but now also for T-Mobile and AT&T through Best Buy) is Google's flagship Android Gingerbread phone, so there's no surprise here that the zippy smartphone bears a straightforward Android interface.