First navigate to your chosen room from the rooms list.
You will see a large camera icon at the top left of the screen.
Tap on the camera icon which will activate the camera app.
Take your room photo. It will auto-save, just close the camera when you are done. You can take several photos consecutively without closing or saving.
A thumbnail of your photo will appear.
Your can tap on this thumbnail to review your photo.
From here you can delete or re-take the photo.
You can also re-lable the photo in the caption box underneath.