The technology behind an AN weather app

In the QPC mobile ANW video they show many examples of how people will
linteract with digital content in the future. Some of them aren't
possible with current smartphones but one is: knowing the weather.

One of the new features of smartphones are motion sensors. Phones can
detect if they're being titled upwards. People don't usually tilt their
phones upwards, but if they do they'll either be pointing at a ceiling
or the sky. The sky is relatively easy to recognise even with the basic
cameras available on smartphones. The spectrum of sunlight is very
different to a ceiling. The intensity and colour of light is different
to artificial light sources. This system might be confused by daylight
lightbulbs though I think there are other facets of the spectrum of
natural light that mean a software program could identify natural light
from daylight-corrected fluorescent light; admittedly the sensitivity
and spectrum of phone cameras may be a weakness. Taking a third bit of
information about position from the GPS sensor can make the system
totally reliable, and reliability is important for AN applications.

This use of the new sensor data available on smartphones means the
application can detect a person pointing their phone at the sky. At
night people may want to use AN astronomy applications which are already
in production but during the day there's no other reason to point a
phone at the sky. This makes the logic very simple and reduces the need
for any extra button press or interaction.

Soon every phone will bring up the weather forecast when it's pointed to
the sky. It will become totally natural.