in App purchase | in App billing

Question

I am working on in-app-billing from my android phone. I am signed in with my google account and i can buy any in-app items (from other apps like games etc). But, when I tried to use in my app it is not working...getting error "Authentication is required. you need to sign into your Google Account."

For other application it is working but not for me. What do I need to do here? Log I received:

D/IabHelper: Starting in-app billing setup.
D/IabHelper: Billing service connected.
D/IabHelper: Checking for in-app billing 3 support.
D/IabHelper: In-app billing version 3 supported for 
D/IabHelper: Subscriptions AVAILABLE.
D/IabHelper: Starting async operation: launchPurchaseFlow
D/IabHelper: Constructing buy intent for com.example.purchased, item type: subs
D/IabHelper: Launching buy intent for com.example.purchased. Request code: 10001

Answer 1

Please make sure you have downloaded your app from Google Play. If you run your app in debug mode and try to purchase, you will get authentication problems.