Build a manageable Newsstand base app (iOs)

Project Detail: A colleague of mine is aiming to launch an e-magazine next year on an iOS Newsstand (and Kindle). We are building our issues around inDesign. Criteria: Work involves developer to create an easy to maintin solution for exporting the finished issues from inDesign (including multimedia and light interactive features such as galleries and weblinks ... no games or anything too complex) into an iOS Newsstand App. Key Points: 1. One must be able to update the Newsstand App with each issue either via custom intermediate app on OSX, or via updating folders and files in Xcode, rebuilding and submitting the update to apple. 2. The base iOS app should have the capability of an app purchase subscription options and push notifications for new issues. My colleague is capable of using Xcode to tweak, build, submit and modify apps. Additionally, I welcome any suggested solutions as well. If interested, let me know at the earliest on your proposed solution and your quote (time and cost).