What are the main power draws within a mobile phone radio?
Very nice  study.  

Slides:

An Analysis of Power Consumption in a Smartphone

PDF of same



Conclusions:


Major consumers: 

display &amp; cell radio

WiFi power low in most situations

CPU can be significant

Future power driver
Where power is not going:
RAM
Audio
Bluetooth
Storage




Korean study.
 27 slides -  results differ somewhat from above.



Energy tradeoffs in smartphone apps

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