So now that Apple's finally addressed (well, sort of addressed) the 800-pound gorilla known as multitasking, it's time to take a good, hard look at how iPhone OS 4 stacks up against Redmond's completely redesigned mobile monster that's destined to hit handsets toward the end of the year. Though the two companies have taken vastly different paths to get to where they are with their mobile strategies today, there are some striking similarities between the platforms; take that multitasking we already mentioned, for example -- both iPhone OS and Windows Phone are looking to keep processor and battery utilization to a minimum by putting the emphasis on managed services for background apps rather than just letting them run roughshod over your fragile hardware. Of course, there are some striking differences, too -- so let's have a look, shall we?