Noida-based handset maker Ringing Bells has unveiled 'Freedom 251', the world's cheapest smartphone, priced at ₹251. The 3G-enabled Android phone sports a 4-inch qHD display, 1 GB RAM, 3.2 MP rear camera, 0.3 MP front camera, 8 GB in-built memory and is powered by a 1.3 GHz quad-core processor. It will be available on company's website between February 18-21.