Closing apps in iOS 4 to save battery

Like most tech geeks out there I was keen to update to iOS 4 on my 3GS as soon as it came out. The two negative things I noticed were 1. My contacts and calendars had all gone and 2. My battery was only lasting half a day (usually I get about a day). The first turned out to be a problem with gmail synced contacts and calendars. A reset of the exchange account seemed to help as contacts were coming back in blocks of 50 and calendars had returned. After an hour or so everything was back to normal here.

It took me a day or two to realise that the battery was draining at a much faster rate since the update. I put this down to multitasking but it never occurred to me that you could kill open apps. It was only once I found this article on how to do it and closing the open apps did my battery go back to lasting the day. I hope this helps others like me that didn’t find it obvious.

Pressing on an open app for a few seconds in the multitasking bar brings up the close app icon.