In-app billing. How to store information that user

Question

There was a similar subject here

Okay. We can find out about user's purchase using RESTORE_TRANSACTIONS request to Google Play. But. It is written in documentation that " You should use the RESTORE_TRANSACTIONS request type only when your application is installed for the first time on a device or when your application has been removed from a device and reinstalled." Why not after every start? It looks comfortable and possible to query Google Play every time when the app starts.

Otherewise

1) I should store information about payment on my WEB server

2) Or I should save this info to sdcard. The record should be secure, including device ID, so that copy on another device will not work

So. Which way is better? Thanks.

Answer 1

I would suggest:

3) Use the in-app Shared-Preferences Class or SQLite Database

(Check this page: http://developer.android.com/guide/topics/data/data-storage.html)

Encryption is always good, but this way the data is so to say attached to your application and can usually not be accessed by other apps.