Apple's ($AAPL) CareKit, which is aimed at helping patients better track their own health, was announced last month. Now it's started rolling out. And four iPhone apps are integrated with it already: two Glow apps, one that tracks an infant's symptoms and the other that sends that information to a pediatrician; the Start app for monitoring depression medication adherence; and One Drop, a diabetes app to track glucose, food, insulin and activity. More