We’ve come to expect China-based Gionee to push the boundaries of smartphone slimness. The Elife S5.5 and its successor, the Elife S5.1  – the model numbers indicate their slimness in mm – are examples from the recent past. However, other Chinese brands such as Oppo and Vivo have launched even thinner models and the title of the slimmest smartphone now lies with the Vivo X5Max . This...