There have been at least a couple of underlying core concerns in the world of smartphones since the category exploded. One is whether the great guns of the hacker and cracker world will be turned with full force toward these enticing devices. Another is whether all the great and snappy things of which cutting-edge mobile devices are capable will be truncated by the fact that there is not enough power to drive them for a reasonable length of time.
The battle to keep batteries from being overwhelmed is a numbers game. Hossein Falaki, a Ph.D. candidate in the Computer Science Department of the School of Engineering and Applied Science UCLA, pointed to three variables that control the life of smartphone batteries: transistor density, the energy density of batteries and the increase in available bandwidth.
Over time, the strength of batteries - the energy density - is expanding more slowly than the others. "On mobile phones, the capacity of [lithium-ion] batteries have been increasing only linearly during the past few years and they are unlikely to keep up with the exponential pace of energy demand on smartphones," wrote Falaki in response to emailed questions. "Therefore, as smartphones become more and more capable in terms of computation, communication and display resolution, average battery lifetime is getting shorter."
Two studies released in mid-March by J.D. Power and Associates suggests that the type of shortcomings suggested by Falaki may be coming home to roost for vendors and carriers. The two studies suggest a strong link between subscriber satisfaction and the length of battery life. Battery life proved to be the least satisfying element of smartphone satisfaction and the only attribute that is receding over time. In other words, people are not happy about how long their batteries are lasting, and that is the only thing they are unhappier about now than in the past. The score for this attribute, the company said, has decreased from 6.9 in September 2011 to 6.7 in the recent rating, which is based on a rating of 10.