Phonemakers bank on virtual reality, add-ons to ignite sales

From a remote-controlled robot camera to a sonar-enabled smartwatch to locate fish to reel in, smartphone makers are launching new devices and services in a bid to drive sales for their handsets and set themselves apart in a crowded field.

Waning global demand for smartphones, especially in key markets such as China, and margin-eroding, cut-throat competition are ratcheting the pressure on manufacturers to find ways to convince consumers to pay up for a little bit extra.