The short battery life endured by smartphone users is the fault of software developers rather than battery manufacturers, according to a leading academic in the field.
David Jazani, senior lecturer and link tutor at The University of Bedford's computer science department, believes that the flack directed at battery manufacturers is unjustified.
"Software is frequently written with complete disregard for the battery," he told Computing.
"This is particularly true in the case of smart devices."
Battery manufacturers are caught between a rock and a hard place. Users of smart devices want bigger screens, better processors, faster connectivity and more accurate geo-location, but there is a limit to the rate at which the current lithium-ion battery technology can advance to meet these needs and still be safe.
Jazani doesn't blame the hardware manufacturers for this predicament. They are constantly driving efficiencies so that they can offer new features. However, software engineers play by different rules.
"Continuous updating of the apps, adware and checking with the network is unnecessary. Free apps are even worse and demand information to be uploaded as well as often being advertisement-driven; they download new ads with total disregard for battery depletion," Jazani said.
The end result of app developers' profligacy with battery resources is the familiar frustration in which people are unable to send an important email or call home to warn of a train delay as the phone they had charged in the morning has died.
With a little more attention to detail on behalf of the developers, things could be very different, Jazani said, suggesting that all apps should be given a battery depletion rating, both for when they're active and when they're running in the background.
"It's very easy to measure," he said.
Such a rating scale would focus developers' minds, persuading them to tweak parameters such as quality of animation, resolution and colour palette in favour of lower consumption. Constant calls to Wi-Fi and geolocation are also wasteful, as are unnecessary adware downloads.
Battery life for many smartphone users is worse than it was five years ago, since when the number of apps has ballooned. While users can be vigilant about manually turning off Wi-Fi and location services when not needed, perhaps the most helpful thing to remember is that, as with lunches, there's no such thing as a completely free app.