Generated Zip file Downloading from a server on iphone?

My iPhone app will download a zip file from server and it will unzip itself. But the thing is that zip file on the server will be generated by the request of the开发者_高级运维 app and it can be take up to 20 seconds.

So my question is which one is more useful and why?

1. Requesting from server and wait until it generates and download.

2. Request from server. Get a generated file name. Request for that file every 5 or 10 seconds.

Any other solutions will be appreciated. Thanks for your help Engin

If you're doing an asynchronous request (which you should) then option 1 is alright.

If you only want save traffic of server and client, not need zip, you can use gzip/deflate support of you web server. Easy and quick. Client do not need do anything.