What is Android In-App Billing?
Android Market In-app Billing is an Android Market service that lets you sell digital content in your applications. You can use the service to sell a wide range of content, including downloadable content such as media files or photos, and virtual content such as game levels.
Why In-App Billing?
Using In-App Billing you are free to use Android Market Application to sell your application's content.When you use Android Market's in-app billing service to sell an item, Android Market handles all checkout details so your application never has to directly process any financial transactions.
Android Market uses the same checkout service that is used for application purchases, so your users experience a consistent and familiar purchase flow.
What Android Market takes from you for this service?
The transaction fee for in-app purchases (i.e is same as the transaction fee for application purchases )=30%.
What You need for doing In-App Billing (or In-App Purchases)?
Before you get started with in-app billing, be sure to review the following requirements and limitations.
No, As for now there is no free account available for Google checkout for testing your In-App Billing application. Don't be confuse with sandbox account for Google checkout as they can be used with only Web Applications. We can't use the Merchant Key and Merchant Id in place of public key (explained later in this post) in our security.java file.
Structure of In-App Billing in your Application:

Android Market In-app Billing is an Android Market service that lets you sell digital content in your applications. You can use the service to sell a wide range of content, including downloadable content such as media files or photos, and virtual content such as game levels.
Why In-App Billing?
Using In-App Billing you are free to use Android Market Application to sell your application's content.When you use Android Market's in-app billing service to sell an item, Android Market handles all checkout details so your application never has to directly process any financial transactions.
Android Market uses the same checkout service that is used for application purchases, so your users experience a consistent and familiar purchase flow.
What Android Market takes from you for this service?
The transaction fee for in-app purchases (i.e is same as the transaction fee for application purchases )=30%.
What You need for doing In-App Billing (or In-App Purchases)?
Before you get started with in-app billing, be sure to review the following requirements and limitations.
- In-app billing can be implemented only in applications that you publish through Android Market.
- You must have a Google Checkout Merchant account to use Android Market In-app Billing.
- If your device is running Android 3.0, in-app billing requires version 5.0.12 (or higher) of the MyApps application. If your device is running any other version of Android, in-app billing requires version 2.3.4 (or higher) of the Android Market application.
- An application can use in-app billing only if the device is running Android 1.6 (API level 4) or higher.
- You can use in-app billing to sell only digital content. You cannot use in-app billing to sell physical goods, personal services, or anything that requires physical delivery.
- Android Market does not provide any form of content delivery. You are responsible for delivering the digital content that you sell in your applications.
- You cannot implement in-app billing on a device that never connects to the network. To complete in-app purchase requests, a device must be able to access the Android Market server over the network.
No, As for now there is no free account available for Google checkout for testing your In-App Billing application. Don't be confuse with sandbox account for Google checkout as they can be used with only Web Applications. We can't use the Merchant Key and Merchant Id in place of public key (explained later in this post) in our security.java file.
Structure of In-App Billing in your Application: