iOS doesn’t yet permit apps like Instapaper to automatically download new content in the background on a regular schedule, but Background Update Locations can get most of the way there for a lot of people. Simply add up to 10 locations that you enter and leave often, and Instapaper will frequently update without manually launching it.
According to Apple, it’s not OK to let the user set a predictable schedule for downloading new content. But it is OK to have a more complicated user interface, and needlessly fire up the GPS chip, to produce a semi-predictable schedule. Meanwhile, the built-in Mail app can check for new messages on a repeating schedule, but third-party apps cannot. See also the background music kludge.