It certainly looks very similar to bertus' exercise bike reference. I've got one very like it on my step exerciser but the fact that the device shown here logs distance rather than steps as mine does, probably says it is not a step exerciser.
How I think it works. Work done (energy in calories in this case) is F x d (force x distance) so the device counts an impulse from the pedal of the exercise bike or the mat of the tread mill that tells the device what distance has been covered. The exercise bike will have a built in friction that will be the force that has to be overcome, or the treadmill will have an incline having the same effect. The device presumably knows somehow what the friction force is so can easily work out energy used.
The device clearly has a timer, hence the time display and the speed display. The display does not seem to indicate power output but that would be an easy thing to compute (Power = energy / time ) and would make it much more interesting. Could I power a light bulb or an electric kettle?
(Hint --- It will just be a light bulb! Only Olympic sprinters can top a Kilowatt!. The rest of us are down in the 100Watts or so.)