Method that takes an ALAssetLibrary group name as a string and returns the last ALAsset entered for that group.

iOS5: ALAssetLibrary Group Parser for Most Recent Asset

-getLastAssetFromCustomFolderWithName:(NSString*)folderName{
   if(assets == nil){
        //Used to collect our applicable assets
        assets = [[NSMutableArray alloc] init];
        
    }
    
    if(library == nil){
        //
        //The lifetimes of objects you get back from a library instance are tied to the lifetime of the library instance.
        //source: http://developer.apple.com/library/ios/#documentation/AssetsLibrary/Reference/ALAssetsLibrary_Class/Reference/Reference.html
        //
        library = [[ALAssetsLibrary alloc] init];
    }
    
    NSAssert(library, @"Unable to open ALAssetsLibrary");
    
    [library enumerateGroupsWithTypes:ALAssetsGroupAll
                           usingBlock:^(ALAssetsGroup *group, BOOL *stop){
                               if([[group valueForProperty:@"ALAssetsGroupPropertyName"] isEqualToString:folderName]){
                                   
                                   NSLog(@"GROUP NAME: %@", [group valueForProperty:@"ALAssetsGroupPropertyName"]);
                                   
                                   [group enumerateAssetsUsingBlock:^(ALAsset *asset, NSUInteger index, BOOL *stop)
                                    {
                                        if (asset) {
                                            NSLog(@"ASSET, %@", asset);
                                            [assets addObject:asset];
                                        }
                                        
                                    }];
                                   
                                   dispatch_async(dispatch_get_main_queue(), ^{
                                       for(ALAsset *asset in assets){
                                           NSLog(@"ASSET CREATION DATE: %@", [asset valueForProperty:@"ALAssetPropertyDate"]);
                                           
                                       }
                                       
                                       NSLog(@"ASSETS COUNT: %i", [assets count]);
                                       if([assets count] > 0){
                                            //HAVE ASSETS, GO!!
                                            //Last asset is most recent (just saved)!
                                            NSLog(@"LAST ASSET: %@", [assets objectAtIndex:[assets count]-1]);
                                            [self doSomethingWithAsset:[assets objectAtIndex:[assets count]-1]];
                                           
                                       }
                                   });
                               }
                               
                           }
                         failureBlock:^(NSError *err){
                             NSLog(@"err=%@", err);
                         }];
}