I encounter a problem by following your comment. I would like to download different file at same time with different delegate:

.h:

```
NSMutableData *fileData;

```

.m:

```
NSString *imgfile = [NSString stringWithFormat:@"http://xxxx/01.jpg"];
NSURL *fileURL1 = [NSURL URLWithString:imgfile];

NSString *audiofile = [NSString stringWithFormat:@"http://xxxx/01.mp3"];
NSURL *fileURL2 = [NSURL URLWithString:audiofile];

NSURLRequest *request1 = [NSURLRequest requestWithURL:fileURL1 cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10.0 ];
NSURLRequest *request2 = [NSURLRequest requestWithURL:fileURL2 cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:10.0 ];

NSArray *connections = [[NSArray alloc] initWithObjects:
[[NSURLConnection alloc] initWithRequest:request1 delegate:self ],
[[NSURLConnection alloc] initWithRequest:request2 delegate:self ],
nil];

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
    fileData = [[NSMutableData alloc] init];
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
    [fileData appendData:data];        
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
    NSLog(@"Unable to fetch data");
}

```

ok, the download process works, but, the file size of jpg and mp3 are incorrect, the only correct thing is the total file size (jpg+mp3), please could you have a look on the code, what is missing? 

Another question is, I put the file in a NSMutableArray, my question is, how to check which index of array is the correct file type (jpg and mp3)? because I need to save them to the device folder.