The cheapest android phone I can find seems to be sold for 32.17$ (Rs. 1,999) in India (http://gadgets.ndtv.com/mobiles/news/jivi-launches-cheapest-android-based-smartphone-in-india-at-rs-1999-594264).
On what platform?
Likely Android and IOS.
The cheapest android phone I can find
The cheapest android phone you can find is used, a few years old, and your neighbour is selling it for 5 euros...
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