Chinese manufacturer ZTE has revealed a smartphone called the Blade A1 which the firm says is the world's cheapest phone to feature a fingerprint sensor and 4G capabilities.Priced at just under $100, the phone has a 5-inch HD screen with a resolution of 1,080 x 720 pixels. It hosts a quad-core MediaTek MT6735 processor, which is clocked at 1.3GHz and is paired with 2 GB of RAM.The rear-mounted fingerprint sensor on the ZTE Blade A1 is the same one used on the Axon phone – the FPC1025 – is able to unlock the device in just 0.3 seconds, courtesy of its 360-unlocking technology.In July, ZTE announced its Android smartphone Axon featuring FPC's touch fingerprint sensor FPC1025 and Precise Biometrics' software.