title: How can I use Appstore API to get top100 list? What is the common architecture to build a appstore application website?
body: <ol>
  <li><p>I've found a PDF file of Appstore search API, that I can use some parameters to fetch an application's detail information.(sorry I forgot the download url, but I found it in stackoverflow)<br>
  But there are so many sites that show you a Top100 list(like appshopper.com), and such as Mobclix.com also provide you the rank information.How can they do that? I didn't find the related API in the PDF file.<br>
  I also found an Appstore API by ABTO(<a href="http://www.abtollc.com/AppStoreAPI.aspx" rel="noreferrer">http://www.abtollc.com/AppStoreAPI.aspx</a>), but I really wanna do it by myself.</p></li>
  <li><p>If I clear the 1st question, then I'd like to know the common architecture of building a website based on the appstore data. Do I need a database to cache the appstore's data, and create a batch to fetch the data frequently, execute like once per hour? I think it might not be clever to access the appstore for every user request, and may be there is a access limit of appstore?</p></li>
  </ol>
  
  <p>Thanks for your help!</p>