WD My Passport Wireless offers a simple to use web access panel through which you can simply modify ample of settings and make changes in the drive output. Now there is a option through which you can switch off drive through your Smartphone or tablet without pressing the power button. But you cannot turn it on through mobile. It only works on the turn off part. It is convenient sometime. Restart is also available in the same section. IF the drive is working slow or having some buffering problem then you can reboot it and reconnect to check the output.
Start with connecting your device with the hard drive through Wifi. The process is same here. Go in the wifi section and from there you have to look for MyPassport. The default SSID of the hard drive. Tap on that for connecting. Then start your web browser and in that type mypassport.local or 192.168.60.1 to open the web access panel.
Now tap on the Hardware section. Scroll down to the bottom. Below you can see a Power section. Just below that lies two button for Shutdown and Reboot. You can hit Shutdown to switch off the drive whenever you want.