Background fetch regularly

Question

I want to upload the location in background every 30secs to 1min. Is it possible? I have found that I can set UIApplicationBackgroundFetchIntervalMinimum. But I looked around this constant to tell the device to fetch about every 30mins. Any way to do that? Thanks.

score 0 · Answer 1 · answered Jul 17 '17 at 14:29

I don't know the exact purpose of yours for uploading location for every 30 secs. It's not recommended to do so. I think you can go for MonitoringSignificationChanges in CoreLocation framework. It will give you update whenever there is a significant change in location. It helps in saving the battery.

Starts the generation of updates based on significant location changes by the following method:

func startMonitoringSignificantLocationChanges()

This method initiates the delivery of location events asynchronously, returning shortly after you call it. Location events are delivered to your delegate’s locationManager(_:didUpdateLocations:) method. The first event to be delivered is usually the most recently cached location event (if any) but may be a newer event in some circumstances. Obtaining a current location fix may take several additional seconds, so be sure to check the time stamps on the location events in your delegate method.

Fore more info: Apple Docs

I tried already. If the user doesn't move, this delegate method won't be called. I even tried using silent notifications to tell the app to update. After sending for a while, APNs server will stopping sending for about 20mins. And I also tried timer. — Carl Hung, Jul 17 '17 at 14:31
@CarlHung you should *not* even do it, https://stackoverflow.com/questions/41021733/is-using-core-location-for-performing-functionality-in-the-background-appropriat — Ahmad F, Jul 17 '17 at 14:33
Sending silent push notifications too many times won't guarantee of delivery through APNS. If too many requests it simply ignore — Sivajee Battina, Jul 17 '17 at 14:41

score 0 · Answer 2 · answered Jul 17 '17 at 14:47

Your approach has multiple problems. Most apps are not allowed to run continuously in the background like you want to do. You get ~3 minutes of background time, and then your app gets suspended. Navigation apps are an exception. If your app is a navigation app you are allowed to run continuously in the background.

Polling the GPS every 30 seconds is also a bad idea unless you're a navigation app. You'll quickly drain the user's battery.

Likewise uploading the user's location every 30 seconds will keep the cellular/WiFi radio on the phone powered up nearly constantly, which will drain the user's battery quite rapidly.

Background fetch regularly

2 Answers2