Short and sweet, loved it. There are so many little touches that make this great.
With just a camera and a compass, navigation was an interesting challenge.
Photos getting distorted while turning due the camera's slow shutter speed was very impressive.
Really effective use of sound. The first few times I thumped into a wall; the sound was enough to scare me. I was attuned to every little thing I heard.
The way it started off was unnerving, and the reveal to what was wrong was awesome. In a completely static environment, seeing something move shocked me.
Once I was past the horror aspect of the game though, trying to finish was a little tedious. After the game was out of surprises, I spent a while wandering trying to find my way back to base, killing the mood a bit.
Y'know how real Roomba's build a digital map of their surroundings? Perhaps each photo could have added to a sparse 3d scan that you could see after a photo was taken. If you took a photo of something moving, you'd have a distorted image frozen in time until you took another photo in the same spot. Mapping out the house would be another sense of progress, besides cleaning debris, and would make the endgame swifter.
Don't let me backseat dev you too much though, this was a great concept and great execution.