You used to be able to tell how serious a photographer was by the size of his camera. All that is changing. Cameras are getting better and smaller and although quality of cameras can be quite a subjective thing, nobody can deny the leaps that are being made. Earlier this year Sony introduced consumers to compact (system) cameras with full frame sensors with the Sony A7, A7r and later the A7s. Full frame sensors used to be the exclusive territory of big mirror reflex cameras but you can now take the (technically) same photographs with a camera that is much smaller and much lighter.
And now there is the OnePlus One phone, a (for the moment) invite only Android CyanogenMod phone with a quite impressive camera. Some owners decided to put it to the test against the Canon 5D Mark III, probably the most popular professional full frame camera by Canon with a price tag of around $4000,- and weighing more than 2 lb.
See the videos to make up your own mind (watch fullscreen and in HD for best quality):
In all fairness this is a comparison between the Canon 5D’s 1080p footage and the 4K video from the OnePlus so there is bound to be a noticeable difference in detail, even scaled down. On the other hand you can see how the Canon has a better dynamic range.
Regardless, the OnePlus makes an impressive statement. There is something to be said for the argument that at some point there simply needs to be physical surface to collect photons and lenses need to be able to curve light, but then again, what the OnePlus does today would have been called impossible 10 years ago.