Android InApp Billing - what are really nonces for?

Question

YES, I\'ve read all the docs @ developer.android.com and I do understand it all with one basic exception - what it was introduced for.

Since all order responses from Goo

Answer 1

You should be saving the generated nonces before sending them. Android apps can crash or be shut down at any point so in general everything should be saved.

The reason for using nonces is to prevent replay attacks. I´m far from qualified to answer whether to using the nonce is neccesary or not but I assume it's there for a reason.