I would say the WiFi app may be great!
Sony implements cable release over that "mini USB2" and that works fine, but you still need mess with cables. Having a phone app for exposures may be a great thing!
I have an H4D-50, a Sony RX100M3 and a Go-Pro camera.
On the H4D-50, I use a 8€ remote control. It is quite light, does not need batteries and takes very little place in the bag. It is a bit unhandy to plug it in, due to the position of the connector on the camera, but it does the job. Basically, on somewhat static subjects, I raise the mirror and use the remote to make sure there are no vibrations.
On the Sony RX100M3, I have used the built-in wifi a few times. It needs an app on the iPhone (or Android). It needs half a minute or so to connect once the camera wifi is on and then streams the camera viewfinder on the phone. There is a small delay between the button press on the phone and the actual shutter release. The distance at which the connection is lost is surprisingly small, less than 5 meters or so (so less than what would be needed for a wildlife trap, for example). The system empties the batteries quite fast on both the camera and the phone, so I need to switch it off between takes to conserve power (and then wait to reconnect, etc). Last but not least, an iPhone is surprisingly inconvenient to use outside, especially when it is raining a bit or quite cold.
On the Go-Pro camera, I use the built-in wifi to adjust settings (the camera lacks a decent built-in interface). The app, different from the one for the Sony, behaves in a similar manner. Range is much better, at least 50 meters.
On both the Sony and the Go-Pro, the app is sometimes upgraded to a new version together with the other apps on the phone. Sometimes, that also requires that the camera firmware is upgraded, which is a rather complicated process and cannot be done in the field. I had the inconvenient surprise once to find out away from home that the new app would refuse to communicate with the old firmware, so I had to do without the wifi for that session.