Compare these two images:
Both taken in very similar lighting, using the camera on my phone, in the same place. The one on the left was taken yesterday, the one on the right today.
The difference is down to me cleaning the crap out of my phone's case. A couple of months ago I changed the battery on my phone and wasn't very careful about cleanliness when reassembling. I finally got round to taking it apart and wiping all the dust off the inside of the lens. No more soft focus 'art' shots for me.