[リジェクト] 2.23: Apps must follow the iOS Data Storage Guidelines or they will be rejected

Appleのホスティングサーバからファイルをダウンロードするアプリを申請した際に、リジェクトされた。

ーーーーーーーーーーーーーーーーーーーーーーーーーーーーー
2.23


We found that your app does not follow the iOS Data Storage Guidelines, which is required per the App Store Review Guidelines.



In particular, we found that on launch and/or content download, your app stores 38.93MB. To check how much data your app is storing:



- Install and launch your app

- Go to Settings > iCloud > Storage & Backup > Manage Storage

- If necessary, tap "Show all apps" 

- Check your app's storage



The iOS Data Storage Guidelines indicate that only content that the user creates using your app, e.g., documents, new files, edits, etc., should be backed up by iCloud. 



Temporary files used by your app should only be stored in the /tmp directory; please remember to delete the files stored in this location when the user exits the app.



Data that can be recreated but must persist for proper functioning of your app - or because customers expect it to be available for offline use - should be marked with the "do not back up" attribute. For NSURL objects, add the NSURLIsExcludedFromBackupKey attribute to prevent the corresponding file from being backed up. For CFURLRef objects, use the corresponding kCFURLIsExcludedFromBackupKey attribute.



For more information, please see Technical Q&A 1719: How do I prevent files from being backed up to iCloud and iTunes?.


It is necessary to revise your app to meet the requirements of the iOS Data Storage Guidelines. 



Aso,
ーーーーーーーーーーーーーーーーーーーーーーーーーーーーー

アプリのホームディレクトリ直下のDocumentフォルダは使用しない方がいいみたい。
DocumentフォルダはiCloudに保存する対象になるのでそこに無駄なファイルを置くと、iCloudの容量を圧迫してユーザーにとって好ましくないかららしい。

■対処
cacheフォルダに保存場所を変更


ちなみに、申請したアプリはこちら

アプリ内で本を購入するとAppleのホスティングサーバからファイルをダウンロードし、
本を読むことができる。