While most phones keep getting bigger, the Unihertz Atom does the opposite. Billed as the world's smallest, it's a ruggedized, water- and shock-proof device running Android Oreo. The screen is a refreshingly small 2.45 inches — the entire device is less than four inches tall and under two inches wide — yet it doesn't skimp on features. There's an octa-core CPU, a 16-megapixel camera, NFC, a fingerprint sensor, dual SIM slots, and all the other features you'd expect from a modern smartphone. Just without the window-sized display.