DOES your favourite app seem to be taking longer to
load than it used to? That may be due to ever-richer graphics and
overloaded cellphone networks, which take their toll on smartphone apps
and increase the time they take to boot and retrieve information from
the network on, say, train times or the weather.
A way to make them boot faster,
developed at the University of Massachusetts at Amherst, could mean your
app might one day be ready and waiting for you the moment before you
need it.
Tingxin Yan
and colleagues have borrowed a trick from computer science to achieve
speedier loading. Called predictive caching, it involves guessing which
software routines are most likely to be needed for the next stage of a
computerised process - so that the right app is primed to run when
called on, without booting from scratch. The system uses the phone's
location and motion sensors to learn when the user typically runs the
app, Yan will tell the MobiSys conference in Windermere, UK, which starts on 25 June.
Imagine that, as you walk to a railway
station each day, you normally get to a certain street corner and open a
train times app to see if the trains are running to schedule. The
software checks the time you usually do this, senses that you are
walking and preloads the app, with the current train info retrieved by
the time you arrive at the corner on which you normally request it.
In tests, the software cut 6 seconds
from the average 20-second boot-up time for apps on Windows phones -
although it gobbled 2 per cent of the battery per day while doing so.
App author Peter Bentley
at University College London sees issues. "This works great if the
things being cached are entirely predictable. But what happens in an
emergency when you need to use a rarely used but essential app and the
phone has preloaded lots of massive apps which then have to be cleared
first?"
It would be better, he says, if coders
designed apps to boot faster in the first place. It also depends on the
type of app. "I would see this technology better suited to those apps
that are designed to be used for 30 seconds or less and which need to go
online and download/upload new data."
