Are temperature and humidity really that useful? I know many Android phones have had them, but have they really be used? Do they really add much to the device?
I believe temperature sensors are required to get barometric data to altitude[1]. That's why all altimeter watches also have temperature though its usually useless while wearing since its reading the temp of your wrist instead of the air.
On a second note I produce an app (http://www.ullrlabs.com) for avalanche danger evaluation and knowing your ambient air temperature is one factor which is helpful in that process. Though I haven't yet tried to read that value on android phones for the app.
Your first note is irrelevant, since all modern phones have a (hot) CPU running while the phone is active. It's why phones don't rely on their temperature sensors for ambient readings in the first place even if they have them.
to the individual they did not pose much benefit, but to society as a whole they were extremely useful. Through programs like pressureNET, literally opening up new avenues for data recording that never existed before.
In the short term these new sensors will provide more benefits to the consumer, but to the majority they will be something you use 1 or 2 times then forget about.
Why? My phone tends to be warm because of body heat most of the time. Yeah, the shell can sometimes get warm under load, but that’s the exception. I would guess that if not for body heat and with the right placement a temperature sensor could get useful data.
However, with the phone nearly always being transported so close to the body I really don’t see it being useful.
On a second note I produce an app (http://www.ullrlabs.com) for avalanche danger evaluation and knowing your ambient air temperature is one factor which is helpful in that process. Though I haven't yet tried to read that value on android phones for the app.
[1]See pressure altimeter calibration equation: http://en.wikipedia.org/wiki/Altimeter