Skip to main content

Amazon Appstore Postmortem: A Guide to Android Developers

Developer Ernest Woo talks about the advantages and challenges of making games for Amazon

Getting noticed is a constant struggle when you're a mobile game developer. You can bet there's an audience for your game -- but how can you reach them?  One possibility for Android developers is to distribute games on the Amazon Appstore.  I've shipped two Android games so far, FRG and ErnCon, both of which are distributed on Google Play and Amazon Appstore. I wanted to share my experience getting a game ready for Amazon Appstore distribution focusing on the advantages and challenges encountered along the way.

Why Amazon Appstore?

Android developers have long dealt with the simultaneous curse and blessing of fragmentation from different OS versions, handsets with different capabilities, and even a multitude of app stores.  There have been many attempts at third-party app stores in the past like SlideMe and AndAppStore but none have gained enough traction to be worth a developer's time to submit a game and maintain that app store listing with updates… Until Amazon's Appstore, that is. The Amazon Appstore is the first third-party Android marketplace to really gain traction in the face of Google Play.

Here are some reasons why I believe in Amazon's Appstore:

1.It's run by Amazon - Amazon is the largest online retailer in the world.  They have the experience marketing merchandise to consumers. They've built reliable and successful consumer digital services around their core offerings like Amazon Prime (instant video watching), Amazon MP3, and Kindle. They've also built reliable and successful developer services like Amazon Web Services.  Amazon is serious about its initiatives into new ventures like Amazon Appstore.

2.App Review Process - a review process in theory guarantees a baseline of quality for consumers.  Having dealt with many substandard apps and games, I feel such a process is useful in weeding out spammers and other such low quality apps.

3.Kindle Fire - the Kindle Fire is Amazon's first Android device and according to Flurry, is doing well in Android tablet market share. To capture this growing segment of Kindle Fires, distribution through Amazon Appstore is a necessity.

4.Free App of The Day - Amazon's Free App of The Day is its premier promotional opportunity, giving small developers like myself a chance to shine in front of potential customers.  Starting the process is as simple as sending an e-mail and it doesn't take much to get it done.

5.Developer Support - Amazon Appstore Support is very responsive to questions. Questions about my games' submission status are always answered within a day.  Although Google Play has had years to build up a searchable knowledge base, their developer support forums still pale in comparison to actual Amazon employees responding to your individual questions.

Game Submission, Review, and Approval

When preparing FRG and ErnCon for submission to Amazon Appstore and during the approval process, there were some hurdles that had to be overcome:


1.Removal of non-Amazon Appstore market links - if your game links to Android Market for any reason, you will be rejected. This requirement might affect you in unforeseen ways through third-party libraries like Heyzap and TapJoy.  FRG actually got away with Heyzap linking to Google Play during review but I was asked to remove Heyzap when applying for Free App of The Day. TapJoy Offer Walls do support Amazon Appstore but require a little extra setup.

2.In-App Purchases (IAP) - ErnCon is a freemium game relying on in-app purchases to monetize.  Releasing ErnCon on Amazon Appstore was only possible very recently in April when IAP was announced. Amazon IAP is actually easier to integrate on a technical level - Amazon replaces the cumbersome handshaking between application Receiver/Service and Google Play with a simpler black-box PurchaseManager which presumably handles some verification of valid transactions for you. If your game has a server-component you can easily verify transactions via a server-to-server call.

3.Conditionally Enabled Functionality - given the above 2 points with ErnCon, there were a variety of places of the game that did slightly different things depending if you had installed via Amazon Appstore versus Google Play.  This was controlled by adding two string resources as follows:


This allowed enabling and disabling the market-specific Receivers and Services.  For example - note the use of the string resource "AmazonMode":


Various places in code checked whether we were in "GoogleMode" or "AmazonMode" to start the appropriate in-app purchase flow.

4.Easy builds with Ant - although not directly related to Amazon Appstore approval, ErnCon ran into some rejections from Amazon for a variety of reasons stemming from poor QA on my side. I encountered a bug in Eclipse where it would produce a broken APK that would generate ClassNotFoundErrors when run. Apparently some sequence of events in Eclipse causes the built-in APK creator to screw up. This bug, in addition with having to test the outgoing unsigned builds (by signing the manually with jarsigner) and late-night coding at 2 a.m. produced many Amazon rejections. This caused many delays and lots of back-and-forth with Amazon. I initially resisted using Ant to build ErnCon thinking I could save myself a bit of time during development but I had to bite the bullet to write an Ant script after wasting an extra week due to rejections caused by my sloppiness.

5.Kindle Fire UI considerations - although Amazon's developer documentation does a decent job explaining the quirks of the Kindle Fire UI, keep in mind the following points:

  • The Galaxy Tab 7 is NOT a valid test for Kindle Fire UI - the Galaxy Tab 7 reports itself as an HDPI device while the Kindle Fire (and all similarly-sized tablets from now on) reports itself correctly as an MDPI device.
  • The Kindle Fire is a version 2.3 MDPI-large device - this means your Kindle Fire drawables will go in a "drawable-large" directory (since that's pretty much what 2.x supports).  Assets for 10" tablets like the Xoom running Honeycomb 3.2 or ICS will need to make use of the new directory naming convention, e.g. "drawable-sw600".
  • The Back button is hidden in full screen mode - unlike other Android devices, the Kindle Fire's Back button is handled as a softkey by the OS. The Back button is also hidden when running in full screen mode as most games do. If your game UI makes heavy use of the Back button for backwards navigation as recommended by the Android design guidelines, keep in mind the user needs to perform an extra tap to show the Back button.  Luckily, Amazon did not reject ErnCon for completely relying on the Back button to navigate out of certain screens.
  • The top system menu causes application Stop/Start - if you bring down the top pull-down menu to reveal system settings like volume, brightness, Wi-Fi, etc. keep in mind that it causes a Stop/Start of your application. FRG has a bug where the entire game resets if the top menu is shown - I've been too lazy to fix it which is why FRG is not available on the Kindle Fire.

6.Kindle Fire approval is a separate process - note that approval for being available to Kindle Fires is a separate process. Your game can be approved for Amazon Appstore but will not appear on the Kindle Fire until this approval process is complete.  Luckily it takes only a day to happen and if something bad is revealed, Amazon asks you to submit a new version of your game without removing your existing listing.

Amazon Appstore Results


Both FRG and ErnCon have performed wildly different on Amazon Appstore for a variety of reasons:

1.FRG - I started the Amazon Appstore process back when Amazon Appstore was first announced and opened to early adopters. FRG is a free/paid-deluxe game but for Amazon Appstore I decided to only submit FRG Deluxe. FRG Deluxe gained very little traction on Amazon App Store except for when it was promoted as Free App of The Day.  During the promotion, FRG Deluxe racked up 88,000 downloads with a 3.2 star rating. The day after, stragglers actually purchased FRG Deluxe and earned me another $400 in sales. Sales went flat soon after. Although Amazon forces the Free App of The Day apps to the top of the Top-Paid category, sales quickly drop off by the time you fall to the #10 slot.  A few other interesting things happened with FRG:

  • Amazon went ahead and rewrote my entire game description. Honestly their description was much better than mine. They were also fine with me copying that description into my Google Play FRG description. Interestingly, Amazon did NOT rewrite ErnCon's description.
  • Awesome user feedback - the comments currently on FRG in Amazon Appstore were received just during Free App of The Day - many users wrote extremely insightful and honest reviews of the game. They took the time to really lay out what was good and bad about the FRG.  Such deep reviews are NOT possible in Google Play. With your own Amazon account, you can even leave comments on others' reviews if you wish.  A lot of this input was served as impetus to develop ErnCon.

2.ErnCon - overall ErnCon is better executed than FRG with better graphics, a more solid multiplayer component, and more marketing dollars behind it (at least for an indie game budget). Here are some general observations on its performance in Amazon Appstore:

  • Launch announcement fizzle - Luis Levy from Novy PR helped me announce the Amazon Appstore version of ErnCon with a targeted pitch. However, this time even fewer Android sites covered the launch announcement, resulting in a very small amount of downloads from the Amazon Appstore. That's something I've witnessed before in regard to Android sites - they seem to be more interested in covering custom ROMs, new phones and Android OS updates.
  • Freemium woes - being a freemium game unfortunately disqualifies me from Free App of The Day. Although I contacted Amazon expressing interest in giving away in-game currency, I was told that Free App of The Day is currently ONLY for paid apps.  ErnCon will also miss out on 50 percent off promotions and probably won't be shown in the "New Releases" list which seems to only show paid apps.
  • Incremental growth - although given the less-than-ideal launch announcement, Amazon Appstore daily downloads of ErnCon has grown to almost equal Google Play daily downloads. Currently ErnCon is being downloaded about 60-70 times each day on each market.  Amazon Appstore users now make up 33 percent of players since May 22nd.  Other than the Amazon Appstore launch announcement, I am doing zero marketing for ErnCon (I'm spending most of my energy developing the iOS version of ErnCon).  Also, other than in-app purchases and external market links, the two versions of ErnCon are identical.
  • Increased monetization - Amazon Appstore users seem to monetize better than Google Play users. Since release on May 22nd Amazon Appstore users spend 9 times as much as Google Play users. Ultimately it doesn't amount to much money, but such a stark difference is quite remarkable.
  • Better categorization - Amazon Appstore has a number of different categories for games including Multiplayer - a perfect fit for ErnCon. Since there are only about 76 games in the Multiplayer category, it didn't take much to reach #6 in the Multiplayer ranks. No doubt this is contributing to the incremental growth mentioned above.

Ultimately the Amazon App Store experience is an interesting one. I see enough potential with ErnCon's increased monetization and incremental growth to wonder what would happen if I were able to direct all of Woo Games' marketing efforts to an Amazon Appstore launch. I may even consider launching our next game first on Amazon -- or give them exclusivity.


If you have any questions, feel free to leave feedback in the comments below. You can also reach me at

Read this next

Ernest Woo avatar
Ernest Woo: Ernest Woo is the founder and CEO of Woo Games, a Boston-based independent developer focusing on mobile and social games. Ernest's first game, FRG, was a top 20 finalist in 2009's Android Developer Challenge 2. His latest game is ErnCon, a top-down, multiplayer shooter for Android tablets and smartphones. ErnCon can be downloaded for free from Google Play and Amazon's Appstore.
Related topics