The deice creates an ad-hoc network that will be named DSP-W115-XXXX (where XXXX will be device dependent). When connecting to this network, my Smart Plug had the address 192.168.0.20, navigating to http://192.168.0.20/ took me to a login page. The credentials for logging in were: username = Admin, password = pin code printed on device.
After logging in, the device presents a page with some current information about the device:
Firmware Version: 1.00-b11
Date: Nov 17, 2017
Checksum: 0x13A44B58