I\'m trying to integrate Android Market in-app purchases into my app, but unfortunately coming across an annoying error every time I try to purchase a real inapp product.
My experience on this error is:
Make sure to upload the signed APK to developer console.
Make sure to install the signed APK on your device not launch the app in the debugger.
Make sure to create a test account in your developer console.
Setup you testing account
Make sure to create in app billing in your developer console and finally activate the item from the console!!! (this is the one that got me after fully following google's tutorial)
Make sure to set VersionCode and VersionName in the manifest to be the same as the version in the developer console (Alpha, Beta or Production. Drafts does not work anymore). @alexgophermix answer worked for me.
If you're looking for testing payments without actual money withdrawal, you need additionally add your testing account to another special list of accounts "Gmail accounts with testing access", you can find that on play account setting(not project!). On the page where you can see a list of your projects go to settings, and then on "Account details" page (scroll down, it's almost in the bottom of page) you will find the "Gmail accounts with testing access" list.