Equivalent of android volley library to handle multiple simultaneous uploads in iOS

In my current project I need to upload 16 images simultaneously.In android they are using volley library to do this.In iOS how can we do this?.I know it's a bit of complex thing.I have 16 buttons on the UI and user should use any button to upload images at the same time they are selecting images from gallery.So it's like maximum 16 uploads simultaneously.