'World's smallest' 4G phone with fingerprint sensor made

China-based Unihertz has developed a 3.7-inch-long smartphone called Atom which the company claims is the 'world's smallest' 4G smartphone. Atom, which runs on Android 8.1 Oreo, features a front-mounted fingerprint sensor for unlocking and can also work underwater. It comes with a 2.45-inch display, 4 GB of RAM, a 16-megapixel rear-facing camera and an 8-megapixel front-facing camera.