Released in September 2017, this plain black smartphone can withstand a drop from 1.8m onto solid concrete. The CAT S31 may seem a mid-level smartphone with 2GB of RAM and 16GB of storage, the 8MP main camera and 2MP selfie camera may seem of the average spec to many but this device is intended for a different audience. The CAT range of smartphones is built to be rugged and tougher than any other on the market today. The Cat S31 comes with IP68 dust and waterproof rating and equipped with wet finger tracking technology, this smartphone is designed to work anywhere under any conditions.