How Much Energy Can We Save From Prefetching Ads?: Energy Drain Analysis of Top 100 Apps

Recently, there has been a surge of interests on devel-oping techniques and architectures for prefetching ads to potentially reduce the smartphone energy drain by 3G/4G radios from fetching ads. Despite the develop-ment of prefetching techniques, it remains unclear (1) how much smartphone energy do ads consume in popu-lar apps in dominant app markets, and (2) out of which, what portion can we realistically save from prefetching? We present a measurement study of the energy drain of top 100 free apps in Google Play, totaling more than 2.2 B downloads, to re-examine the above two motiva-tional questions for ads energy research. We found the upper bound energy savings from prefetching ads is low: out of the top 100 apps, only 57 apps display ads, which incur on average 3.2 % total energy on ads 3G tails. We further show the already-low upper bound ads energy saving is hard to achieve by ads prefetching as different apps exhibit very different ads behavior. 1