Oppo R5 slimmest smartphone from Oppo is now up for pre-order at 29,990. The Oppo R5 is available for pre-bookings at physical stores from Thursday until January 15. The company as a promotional offer is also offering a back pack with R5 smartphone. At just 4.85mm thick, the Oppo R5 was the ‘slimmest smartphone in the world’ until the recent launch…