All are

*.Android alpha (1.0)
*.Android beta (1.1)
*.Cupcake (1.5)
*.Doughnut (1.6)
*.Eclair (2.0–2.1)
*.Froyo (2.2–2.2.3)
*.Gingerbread (2.3–2.3.7)
*.Honeycomb (3.0–3.2.6)
*.Ice Cream Sandwich (4.0–4.0.4)
*.Jelly Bean (4.1–4.3.1)
*.KitKat (4.4–4.4.4)
*. "L" release(developer preview

these are all android { OS }
which means operating system as 2day

the best OS u need buy now start 4m { icecream sandwich 4.Ov UP to 4.4.4v kikat }or Lolipop as new version 5.0v

which include 1 GRAM for more speed or above 2,3,4,

rathan than 512 RAM
.
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