Despite these leaps and bounds, one thing that hasn't improved is battery life where improvements move at a snail's pace.
Many of the improvements in battery life have little or nothing to do with the battery itself but rather components that are becoming less power hungry with each generation. As an example, the move to dual processors for phones isn't just about raw power. Power conservation is chief among the reasons to bring dual cores to phones and mobile devices. Dual 1GHz processors can deliver similar performance, sometimes better performance, than a single 2GHz processor and use less power in the process.
Screen technology, solid-state drives, lower powered radios, and more all contribute to overall better battery life. The operating system plays a big role as well in managing power consumption.
There have been some strides in low powered Wi-Fi radios to extend battery life, but it is still a big drain and some of the low power modes don't work well with some routers forcing a device to turn up the juice. When your device connects to a Wi-Fi access point, it remains on relatively high power even if there is no data moving back and forth. Routers take turns moving data around when there is high usage, whether it is in a Starbucks or your conference room as everyone sits down and flips open a laptop or props up an iPad.
One potentially promising technology that could address this is being by Duke University researcher Justin Manweiler. It's software based and he calls SleepWell.
Once installed on clients, routers, and access points, the SleepWell software allows the radio to go into a low power mode, or sleep, while it is waiting for its turn to connect for data. Unlike today's low power solutions for Wi-Fi devices, SleepWell takes catnaps, many per second. Even when streaming video, you aren't getting a continuous stream of data when the router is under a heavy load. You are getting bursts followed by periods of inactivity. SleepWell would turn the Wi-Fi radio down during these periods, resulting in longer battery life.
While the software works on existing devices, getting it on routers and access points is a bigger hurdle, but one that the demand for more battery life may make clearing possible.