There are somethings lacking in the current scenario is how to rotate the camera in portrait mode since many people are using portrait mode in their scenes these days and also while using via usb and if the phone is not connected to the internet/Wi-Fi there is always a need to verify your pro-version on every start(the second one is just a suggestion for quality of life upgrade). But the biggest issue I think is that droidcam uses excessive battery life due to which the phone might die out very early if someone is trying to do irl stream for example.
Hi, you can rotate the DroidCam source in OBS itself, using the Transform menu when you right-click it. The phone app matches the camera sensor orientation and connects the camera output directly to the encoder. This is done for efficiency - so as far as you last comment, low CPU/battery has been an important goal for the app and its about as optimized as I can make it.
Make sure you don't max out all the options, streaming at max bandwidth and resolution does require more resources. 720p is actually the best for IRL content. But if you are doing IRL streams, a battery pack is going to be a requirement - this has always been the case with phone streaming apps. A Twitch streamer used my old live streaming app for a 12 hour (outdoors) stream once, so it is doable.
DroidCam OBS is more of a Webcam/DSLR replacement though, ideally the phone is always at 100% charge and connected to power. Dimming the screen also drops CPU usage since the phone preview gets muted by the app.
As for the pro check, it will go away after about a month form download time, the app checks itself during the cancellation period.
I hope that helps.
