objective c - launch/wake iOS app periodically -

objective c - launch/wake iOS app periodically -

i have app runs in background. i'd wake periodically: either @ preset times of day or every n hours. must done without user intervention.

i believe since app runs in background, nstimer not work. how can 'wake' app on periodic basis?

of course, that's possible, , easy implement. technique called background fetch. works - 1) inquire operation scheme wake / start application on times. 2) operation scheme decides , periodically start application , calls

-(void)application:(uiapplication *)application performfetchwithcompletionhandler:(void (^)(uibackgroundfetchresult))completionhandler

3) jobs there, , can trigger local force notification user, new info available.

here great article covers question

objective-c ios7 nstimer