multiple image uploading to server using soap based web service - iphone

Question

I am trying to run image uploading using soap based web service and doing this i face 2 key issue in my app.
Issue 1:- When app uploading multiple images to server and at that time if my application goes in background state than at that time my is stop executing (application suspended state). when i my app goes back from background to foreground state than it again resume my background thread.
Issue 2:- When i try to upload 160-170 images on server from device gallery. i received memory warning after uploading 60-70 images on server. i handle that method and try to free some memory within application and i again start my thread at that time my application crashed. //->> for 2nd issue i add 3 different web service and its too long code so i am not going to share it here. when i check on instrument it generally run on max 2 to 2.5 MB in live bytes but when i uploading thread start it gradually increasing and at some pick point i received received memory warning. my code contains feature of ARC but still i got memory warning issue.
code for issue 1:-
- (void)applicationDidEnterBackground:(UIApplication *)application
{
UIDevice* device = [UIDevice currentDevice];
BOOL backgroundSupported = NO;
if ([device respondsToSelector:#selector(isMultitaskingSupported)])
{
backgroundSupported = device.multitaskingSupported;
}
//NSLog(#"backgroundSupported: %d", backgroundSupported);
if (backgroundSupported)
{
_IsBackground = TRUE;
UIApplication* app = [UIApplication sharedApplication];
bgTask = [app beginBackgroundTaskWithExpirationHandler:
^{
[app endBackgroundTask:bgTask];
bgTask = UIBackgroundTaskInvalid;
}];
// Start the long-running task and return immediately.
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT,0),
^{
while (_IsBackground)
{
//// it contineous run my application within this state.
}
NSLog(#"Background loop ended");
[app endBackgroundTask:bgTask];
bgTask = UIBackgroundTaskInvalid;
});
}
}

Answer 1

1 )
Apple cares very much about battery life on iPhones and iPads, so they are very strict about what can run in the background (which is to say, not too much).
With the current shipping versions of iOS, you only have about 5 seconds to clean up or properly suspend things when your application receives a call to the "applicationDidEnterBackground:" delegate method.
You need to come up with a way to upload your images via a background thread while your app is in the foreground. That means that the only time you can upload images is while your app is visible to the user.
More information can be found in this closely related question.
2 )
For your second issue, it's pretty clear that you are not properly releasing (or setting to "nil", or resetting) some variables that are being used in the process of uploading multiple images, which is why you see memory usage increasing and increasing and eventually killing your app.
You already know about Instruments, but it sounds like you need to get even more familiar with tracking down memory usage and which things in memory are taking up more and more space.