Android app invites/free-codes

Suppose I have a game for purchase on Android Market; is it possible to allow the buyer to send a limited amount of invites or codes to their friends, which will allow them (the friends) to download the game free of charge?

Or is my best bet to make the game free and use in-app开发者_高级运维 purchases and/or codes for account creation (it's a network-based game)?

EDIT: Google has added support for promo codes.

Kaka, I am afraid that there is no direct way.

Here is one way to implement it (albeit involves manual refunds) : 1. You can generate a hashcode as free key which gets generated and sent to the user whenever he buys the product. 2. User can then share the hashcode with few friends. 3. Friends buy the product from Android Market and login to the app. They then enter the "free code" sent by User 1 and submit it in App. 4. You refund the amount if the "free code is valid and is not exceeded the count" manually in Android market.

Not the best solution but works if the number of users are less and you can handle the refunds yourself.

Unfortunately there's not way to let a user install a paid app for free (presumably in case it's exploited to cut Google out, thus costing them their 30%)

Your second option - a free app with in-app purchases - is by far the better option.