As developers, we’re occasionally (okay, maybe more than occasionally) stuck in the middle between designers who ‘know what works’ and executives who ‘know what they want.  Even in smaller shops, it may not be clear which user experience will more often result in the desired behavior. Beyond simple use tracking, testing two different options to determine which works better usually meant two separate APKs and a lot of data mining and management to see which was the best.

Amazon has changed that with the release of the A/B Testing Service, where developers can run experiments within one APK. You define the variables to test in each of two variations, and then decide what percentage of downloads will get each variation. The app then collects data and allows you to make an informed decision about which variation you want to enable. These variations could vary from the speed of the ball in a game, or the message displayed while trying to upsell an In-App purchase item like extra lives. It’s easy to configure and integrate the A/B Testing Service with your app and it’s also free for any developer distributing their apps on the Amazon Mobile App Distribution Program for Android.

In this post, you will learn how to integrate A/B testing into your app. For our example, we will use the “Snake Game”. In the traditional game, the speed of the snake increases every time it is fed.  We will run tests to figure out the optimal speed increment in order to ensure that the game is neither too easy nor too hard for the player and that the player is always engaged.  In our case, a successful test would be if 70% - 73% of players are able to feed the snake 20 times before the snake collided with the boundary or the snake itself. This will give us objective data on whether the increment was too high, too small, or just right.

Creating your test

Once you have identified your test, you can create an A/B test by going to the Mobile App Distribution page to create it.

In our example, we will create a project called “Snake Speed Project” and an A/B test called snakeSpeedTest. We will use this to test out various increments in the speed of the snake until we find the optimal one.

To configure an A/B test you will need the following information:

1. Name of the test
2. Event name to count the number of views
3. Event name to count the number of conversions
4. Variable name for each variation
   1. Variation A
   2. Variation B
5. Distribution percentage

In our example, the test would look like the screenshot below:

For more details on how to setup an A/B test, please visit the startup guide.

Integrating the API

Now that you have a test set up in the Mobile App Distribution page, you’re ready to integrate it into your application. For this, you will need to download the SDK.

After downloading the SDK you will need to integrate it into your project. For more information on how to setup your project, please visit Integrate the SDK.

To initialize the Amazon Insights SDK, you will need to obtain the following from the Mobile App Distribution page:

1. Application key – Which can be retrieved by going to your “My Apps” dashboard and selecting the app. One of the properties available in the General Information is the Application Key.
2. Private Key Which can be retrieved by going to the  app’s A/B testing page and click on “View Private Key”.

You can now initialize the SDK using these two keys.

// Configure the Amazon Insights SDK
AmazonInsights
    .withApplicationKey(YOUR_APPLICATION_KEY)
    .withPrivateKey(YOUR_PRIVATE_KEY)
    .withContext(getApplicationContext())
    .initialize();

Now that your application is initialized, you can start receiving different variations for your test. In our case, it is the increment by which to increase the snake speed. 

//Get a variation allocated for the “Snake Revive Project” experiment and
//retrieve the speed variable.
ABTest
    .getVariationsByProjectNames("Snake Speed Project")
    .withVariationListener("Snake Speed Project",new VariationListener() {
        public void onVariationAvailable(Variation variation) {
           speedMultiplier = variation.getVariableAsString("speedMultiplier",
           "feedingTime");
            //... increase speed.

    }}

); 

 After you have successfully retrieved the variation, you would need to notify the Amazon A/B Testing Service of a successful view. You can do that by simply adding the following code. (Note that snakeSpeedIncremented is the same event we added in the A/B testing portal page for counting views)

 // record when the snake is fed for the first time only (visit)
CustomEvent
    .create("snakeSpeedIncremented")
    .record();

 Once the game ends by either the snake colliding with the boundary or itself, we will check the count of the how may times it was fed. If it was more than 20, then we will record a successful conversion. (Note: snakeLevel20Reached is the same event we added in the A/B testing portal page for counting conversions)

 // record if number of feeds is more than 20.
if (noOfFeeds > 20) {
    CustomEvent
        .create("snakeLevel20Reached")
        .record();

}

 Once you have incorporated the SDK and deployed it through the Amazon Mobile App Distribution Program, you now start collecting data.

In our case, we determined that 95% of the players reached level 20 for both test increments, which suggest that the game play was easier than our target. We ran additional rounds of tests by doing launches with new increments and found that the 1.65 multiplier was the optimal level of difficulty, as the conversation rate was around 71%. Refining the increment amounts to do new rounds can be done by just going to the A/B test page. No new APK is required.

The Start your first A/B test guide tells you how you can start an A/B test, view results, and end a test.

As you can see, setting up and integrating Amazon’s A/B Testing Service is simple and straightforward. The best part is that it’s free for developers of the Amazon Mobile App Distribution Program.

We’ve recently updated our marketing resources available for mobile app developers, providing two new badge styles to promote your app’s availability on Amazon. The badges are available in three colors (black, grey, and white), and are localized for all of the countries where our store is currently available. Please use these badges wherever you promote your app’s availability on other app stores.

In addition to the badges, we’ve posted layered PSD images of Kindle Fire tablets for your use in line with the KindleTrademark Guidelines. You can layer in your app’s screenshots to showcase your app on a Kindle Fire tablet.

To link to your app on the web using the badges, use this link structure:

http://www.amazon.com/gp/product/ASIN number/ref=mas_pm_app_name

Replace “ASIN number” with your app’s ASIN (Amazon Standard Item Number). The ASIN is available on your product page on Amazon.com. Replace “app_name” with your app’s name (and be sure to use an underscore instead of a space). Linking on to your app on the web is currently only available for the US store. Instructions on linking will be available for international stores when their web stores launch.

More details on these resources, including guidelines for use, are available within the Trademark Guidelines on the Mobile App Distribution Portal.

One question developers commonly ask us is how they can grow their business by introducing their app to new Amazon customers. The Amazon team is here to help. Each day this week we’ll offer a tip on how to market your app on Amazon.

Marketing Tip #2: Submit your app to our marketing team for consideration for a featured marketing placement. 

We constantly strive to introduce Amazon customers to new apps they’ll love, thus helping our developers grow their businesses. We highlight apps through our storefronts on mobile devices, Kindle Fire, and Amazon.com and through marketing vehicles like e-mail, Facebook, and Twitter.  For example, as I write this, featured placements include “Highly Rated Apps and Games” and “Featured New Releases,” and your app would be considered for these placements as applicable.  Your app may also be considered for seasonally relevant placements like summer travel, back to school, or learning apps.

If you are interested in a featured placement through our marketing vehicles, we invite you to tell us more about your mobile app by completing our marketing request form available through the Amazon Mobile App Distribution Portal. 

Follow these steps to complete the form:

1) Check the Amazon Specific ID Number (ASIN) for your app on the Amazon.com site.

2) Navigate to the marketing section of the FAQ page. 

3) Click the link to the form available under the question “How do I get my app marketed?” 

4) Submit information about your app for our consideration by filling out the form.  Please include the ASIN number you recorded from the Amazon.com site. 

One question developers commonly ask us is how they can grow their business by introducing their app to new Amazon customers.  The Amazon team is here to help. Each day this week we’ll offer a tip on how to market your app on Amazon. 

Marketing Tip #1:  Start with your best foot forward.  Write an effective app title and description.

The title and description of your app is a key opportunity to impress potential customers.  By writing an effective description, you can generate excitement about your app and increase the number of customer downloads of your app.  This is your chance to sell your app to customers! 

Title

The title is the first thing a customer sees and may even be the term they searched on. It appears at the very top of the product detail page, right above your company name.

• Keep it simple. Don’t include extraneous marketing verbiage such as “MyAppTitle – the best most greatest app in the whole wide world and beyond!!!!!!!!”
• Make it readable. Unless your app has special capitalization (PicSay, SwiftKey, SeekDroid), capitalize the first and last words of the title, no matter what part of speech. Between those words, capitalize each word except for coordinating conjunctions (and, but, or, nor, and for), articles (the, a, an), and prepositions of four or fewer letters.
• Be concise. No more than 100 characters—it’s a title, not a Tweet!
• Be clear. If your app has multiple versions, let your customer know by calling it out in the title (e.g., Premium, Pro, Lite, Donate, Free).

Description

The description provides you the opportunity to sell your customer on downloading/purchasing your app.   Consider your audience. Who is your app’s target customer? Make sure the customer knows you are speaking to their interests.  What is your app’s point of differentiation? What are the key features of the app? Let customers know why this app is special and something they would enjoy or need.

Check out the recommendations we shared with you last year here on the blog for writing an effective description.

Do:

• Always use proper punctuation and grammar.
• Introduce your app clearly and succinctly.
• Describe your app's most notable features. 
• Use conversational language.
• Think about your target customer and highlight features that will appeal to that customer.
• Explain how and why your app will benefit users.
• Show off—don't forget to include the attributes that make your app stand out and feel free to do so in detail.

Don't:

• Refer to your app only as "this app" or "an app"—use your app's full name at least once in your product description
• Make false, hyperbolic claims—this type of marketing rarely works and may hurt your app in the long run
• Just write one single sentence—there's more to your app
• Simply list your app's features, explain why these features are awesome and worth adding to a customer’s app collection
• Exercise atypical or inappropriate language that could mislead or confuse customers
• Use excess punctuation that could distract from the information you are conveying.

Editing App Descriptions from the Distribution Portal

1) To edit your app description from the Amazon Mobile App Distribution Portal, navigate to the My Apps tab. 

2) Select the app you'd like to edit and navigate to the Description tab for that app.

3) Edit your app description and save it.

Note: Effective 08-26-2015 Free App of the Day (FAD) has been replaced with Amazon Underground.

Farkle Dice - Free and Farkle Dice Deluxe (Ad-Free) are two popular and well-reviewed apps in the Amazon Appstore for Android.  Developed by Smart Box Games, the apps present a fast-paced dice game and offer both solo and social gaming experiences. 

Smart Box Games was one of the first developers to join the developer program after the Amazon Appstore launched in March. 

Why did Smart Box Games act so quickly to join a brand new store? Todd Sherman, president of Smart Box Games, said that as a small, independent game company, “Our priority is to make sure the games have beautiful art, professional sound effects, and music, and are programmed to be stable and responsive. We typically have limited resources for marketing.  The Amazon Appstore gives developers like us a chance for success by offering customers multiple ways to explore and find games.”  He added, “For example, you can navigate the store by Top 100 Games, or by category, or through widgets powered by Amazon’s recommendation engine such as ‘Customers Who Bought This Item Also Bought.’ Plus, the first year fee for the developer program was waived.”

Within a few weeks of its publishing, Farkle Dice - Free skyrocketed to the top of the Board Games category and soon climbed the charts under the Top 100 Free Bestselling Games. 

Amazon featured Farkle Dice Deluxe (Ad-Free) on July 23  as the Free App of the Day, a daily promotion in which we make a premium app available to our customers for free and prominently promote the app on Amazon.com and in the Amazon Appstore. 

We set an expectation of approximately 75,000 downloads for the Free App of the Day promotion with Farkle Dice - Deluxe. “Our actual downloads far exceeded that expectation, and we were thrilled by the exposure and the comments from new players,” Sherman said regarding the result of the promotion.  What does it mean for Smart Box Games to have so many new users? “As part of a long-term monetization strategy, we plan to contact those newly acquired users via the messaging function within Farkle Dice - Deluxe when we release our new game later this year.”

In a previous post, we talked about automated marketing for apps in the Amazon Appstore for Android. On top of automated marketing, Amazon is constantly striving to achieve an excellent customer experience through timely merchandising of relevant products across Amazon.com. 

Occasionally, we can market apps from our store in other Amazon storefronts when the content is compelling and the right fit. This placement is a win-win for customers and developers. It brings relevant information to customers and can increase impressions and hopefully downloads of an app for developers. Here is an example of a “right roto,” or an ad that appears on the right of a page, for the TurboTax SnapTax app in Amazon’s tax storefront. 

On top of showcasing the TurboTax SnapTax app, we incorporated a “shoveler,” or a grouping of apps, onto the page where we’re displaying other tax-related apps that we think customers may find useful.  Here is a look at the entire page:

So what makes an app the right fit for placement in other Amazon stores?   Bottom line, the app content must be relevant to and/or complement other content on a page in another Amazon store.  

Since the official launch of the Amazon Developer Portal, we have received tons of positive feedback regarding the developer registration and app submission process.  However, with the large volume of activity, it’s not surprising that developers have a few questions that are not directly answered in our FAQ.  We’ll take this opportunity to answer some of those questions:

Are you required to submit a video along with other multimedia content, such as icons and screenshots?

Although compelling videos can be helpful to customers when they are deciding on which app to buy, they are not required. 

The only multimedia files that are required are:

• Device icon (114x114px)
• Large icon (512x512px)
• A minimum of three screenshots (480x854px or 854x480px each)

The maximum size for each image is 3Mb.  More information about multimedia files can be found here. If you have submitted your app and see the status “Incomplete (Missing Multimedia)”, then it is likely that you did not submit one or more of the required images.  If you believe you have submitted all multimedia files and are still seeing this status, we encourage you to contact our support team.

What is the maximum video size that you can upload for an app? 

The maximum size for a video is 30Mb.  There is a 3Mb limit for video files submitted through the Developer Portal’s web console.  If you want to submit a video that is greater than 3Mb (but under 30Mb), please use your FTP account.  The process to create an FTP account and submit your app video is described here. 

What video formats do you support?  Your FAQ says MP4 H.264- so does this mean you don’t accept any other format?

We require your videos to be stored in an MP4 H.264 encoded format.  This is to ensure an optimal visual and performance experience for your customers.  Remember that these videos will not only be viewed on Amazon’s retail website, but also on mobile devices.  If you upload videos that do not meet the requirements outlined in our FAQ, there may be a delay in your submission review, or your video may not be included on your final detail page.

If you have any additional questions as you go through the Amazon Appstore submission process, please do not hesitate to contact our support team.