Plum Optimax 13 official Pictures. Plum Optimax 13 is a Smartphone of plum. The Plum Optimax 13 Android Tablet. Announced Dec 2018. Features 10.1″ Display, Spreadtrum SC7731 Chipset, 4700 MAh Battery, 8 GB Storage, 1000 MB RAM. Plum Optimax 13 price starts.