This article will take you through the steps of testing in app purchase, Android:
- Make sure your Google account has been added as test account on developer account.
- Login to market.android.com/publish
- Click settings, "Account details"
- Add e-mail adresses to the field "License testing"
- To test purchase in a new version of an existing app upload the new version to Google Play as a draft before you start the test
- Test all in app purchase, test single issues before subscription