Mobile and living room devices today present a varied landscape for developers to consider. One aspect that is particularly meaningful for your customers is where your app installs itself. Some devices, like the current Fire tablets and Fire TV have external storage through memory card slots. Other devices, like Fire TV Stick or older Fire tablets have only their internal flash storage. Running out of storage when trying to install a new app can be very frustrating for people who want to use your app. This frustration is compounded for customers who have added a memory card with lots of empty space and still get an error message that the device is out of space when trying to install. That frustration can quickly find its way into negative reviews for your app.

Luckily, for most apps, Android provides a simple solution. By specifying the installLocation in the app manifest, you can provide your user community with the best experience possible for whatever device they own. This doesn't mean they'lll never run out of space, but it helps best manage the space they have.

 xmlns:android="http://schemas.android.com/apk/res/android" android:installLocation="auto" android:theme="@android:style/Theme.NoTitleBar" package="com.examplecompany.myapp" platformBuildVersionCode="23" platformBuildVersionName="6.0-2704002">  android:name="android.permission.INTERNET"/> ¦ ¦

installLocation can be specified as any of the following:

Achievements unlocked!

Achievements and trophies are available on most platforms today and help build engagement with your players in a few ways. They capture “the moment” for the player when they accomplish something meaningful in the game. And over time, for some players (like the “Achievers” of the Bartle taxonomy) they form a scrapbook, or collection, of sorts that marks their experiences over a variety of games. Finally, they provide another storytelling tool that allows the game designer to guide the user through different approaches to playing the game and exploring the game world, perhaps in ways that might not be obvious—completing a level in a very short time, or only using a certain weapon. 

In our previous installment, we spent quite a bit of time working through setting up leaderboards for your game. Let’s build on that by adding GameCircle Achievements and give your players some goals to strive for.

Take me to your leader…board!

Now that we have GameCircle set up and Whispersync working, it’s time to bring out the competitive instincts of our players with leaderboards. Leaderboards are a staple in the gaming landscape and allow players to compare their scores with all the other people who have played the game today, this week, or ever. Depending on the nature of your game, you can have multiple leaderboards. Retroids has an overall leaderboard, as well as separate leaderboards for each type of control—touch, game controller or Amazon Fire TV remote control—to allow players to compare themselves against people who play the way they do. For another type of game, you might have just a single, overall leaderboard or leaderboards based on level, character class, or whatever makes sense.

Figure 1 - List of leaderboards in Retroids and the Top Scores leaderboard

Setting up leaderboards

Unlike Whispersync, you need to do a little configuration on the Amazon Developer Portal before you can use them. Never fear, the set up work is very easy, but first you need to create your title in the developer portal. You don’t need to publish it or even upload an APK to continue on to the rest of the set up steps. Refer back to the earlier post in this series to set up GameCircle if you haven’t already done that.

So far in our Building Retroids series we’ve looked at detecting and handling controllers and remotes for your Amazon Fire TV game, implementing in-app purchasing to drive revenue, and how to leverage social features such as leaderboards and achievements with GameCircle. Today we are going to look at that how to implement some basic Whispersync for Games features to make your GameMaker: Studio game more convenient and fun for your players.

To the cloud!

Whispersync allows you to easily store information in the cloud—such as player progress and settings. This is convenient for your game customers who play on multiple devices or who, for whatever reason, might uninstall your game and then install it again later.

In the previous post in our series we walked through how to implement in-app purchases in your game using GameMaker: Studio. So now that you have an IAP catalog full of great items and ready to generate revenue, we have to make sure your users stay engaged—and spending. We’ve seen that incorporating social elements into your game is a great way to boost engagement and help drive revenue.

Make your game social with GameCircle

Players today expect social features like friends, leaderboards and achievements. They also expect to be able to play your game on all of their devices without losing their progress and settings. Amazon GameCircle offers several features to improve engagement and retention. Leaderboards allow players to compare scores with their friends (and maybe their enemies) to capture the coveted top score status. Achievements provide mileposts for players to help pull them through the experience and keep them engaged and exploring the game. Finally, Whispersync for Games provides a way to store game progress and settings in the cloud so they automatically sync to every device on which your customers play your game. GameCircle is supported on Amazon Appstore titles running on Amazon devices and other Android devices.

Most mobile games today use some form of in-app purchasing (IAP) as part of their monetization strategy. Using Amazon IAP in GameMaker: Studio is not particularly difficult – once you know how to do it. But getting to that stage takes some careful study and experimentation. Hopefully, I can help short cut that process for you as I describe how I built it for Retroids.

Understanding in-app purchase basics

By now, I’m sure most of us are very familiar with IAP. There are three types of IAP items found in games—consumables, entitlements and subscriptions—with consumables and entitlements being far more common, so that is what we’ll cover here.

Consumable IAP items are things that are used, or consumed, during gameplay. Gold, gems, health, potions, etc. You might by a “Bag of 500 coins” and then use those coins to outfit your character, buy gas for a race car, etc.

Entitlement IAP items are things that are “unlocked” and continue to be available to the player forever after that point. Level packs or special items like a gun, sword or personalization items like a costume or theme pack are common entitlements.

One of the great things about IAP is that your game doesn’t have to deal with collecting the user payment information, authorizing and processing the payment, and all the other aspects of securely managing credit card information on your own. As you can imagine, users may be reluctant to enter their payment information separately in every game they are playing. You can rely on the Amazon Appstore to handle all those backend details and to provide a single place that customers already trust with their payment information.

On Amazon Appstore, as with other app stores, there are parts of the IAP that you configure on the server and parts that you code in the game. Each IAP item is referred to as a SKU (stock keeping unit, which is a legacy retail term for “an individual type of thing you are selling”). This includes the name of the SKU, the price and a few other pieces of metadata. The price that is configured in the Appstore is what the customer will be charged. Your game can’t change that at run time, but you can change it whenever you want—without requiring an app update—on the server.

Now that we have game controllers handled, let’s take a closer look at how to set up your Amazon Fire TV game for use with the Fire TV remote.

Using the Fire TV remote for game input

The Fire TV remote control is available with and without the microphone and voice search button, but since that is reserved for the system both remotes expose the same keys for use by apps.

D-pad and d-pad center button

The circular d-pad on the remote control is accessed in the same way as the game controller d-pad.

      if(gamepad_button_check(global.gamepad,gp_padu))
          {
                 // move up
          }

The select button in the center of the d-pad sends the vk_space keycode.

Last week we covered some of the missing documentation in GameMaker with respect to Amazon Fire TV, detailing what you need to know about basic controller detection. This week, as we continue on my building Retroids journey, we will take a closer look at handling controllers.

A well behaved game should handle controllers coming and going during play. This covers cases where a controller loses connectivity due to range or interference, or if the batteries in the controller die while playing.

To accomplish this, the above code needs to be present in the actual game play rooms as well. This could be implemented in a single object that is used in all rooms of the game.

Last week I shared my decision—in the name of more fun games for the world— to make good use of my commute time and build a Amazon Fire TV and Fire Stick game using GameMaker: Studio.

The GameMaker documentation gives a general overview of supporting game controllers. Finding details on how game controller support works with Amazon Fire TV proved to be a little more difficult. In the next few posts in the series I will provide the missing information, focusing on:

• Basic Controller Detection
• Handling Controllers and Controls
• Using the Amazon Fire TV Remote and Controller Selection

Let’s dive into basic controller detection.

Handling the game controller and remote control on Amazon Fire TV and Fire TV Stick

Using YoYo Games GameMaker: Studio to build PC games that use the keyboard or even a USB game controller is pretty easy and many developers choose to first get their game up and running on their PC. This offers the convenience of easy debugging and very fast edit-build-test cycles. When you want to move to a mobile device or a platform like Amazon Fire TV, however, you are going to have to invest some time to build in proper support for game controller detection.

It all started with a bus ride.

Not long ago, I was looking for a project to occupy my time on my bus commute to Seattle. I have experience with a variety of game engines and writing code doesn’t frighten me, but I wanted to use a new tool and get the entire learning experience. Enter YoYo Games’ GameMaker: Studio.

Jesse Freeman previously posted an overview of some of the frameworks available to make your game development for Amazon devices a lot easier. As many of you already know, game frameworks, also known as “engines”, do various amounts of the technical heavy lifting so you can focus on designing fun and engaging experiences for your players. After all, why should each of us write our own code to display and animate sprites, play sounds or handle the touch screen?

One of the engines Jesse covered was GameMaker: Studio. You can download it for free to check it out, as well as the 60-day trial of the Amazon Fire module to target your games for Amazon Fire tablets and Amazon Fire TV devices. GameMaker: Studio is fully cross-platform and other available modules allow you to target iOS, Linux and all game consoles.

If you are completely new to GameMaker, don’t fret! Shaun Spalding, YoYo Games’ Community Manager, has a great series of tutorials to get you going. That’s exactly where I started. You can get an idea what is possible (which is a lot!) by checking out the showcase of games built with GameMaker. I’ll save you the click and just tell you, “Yes, you can build awesome games with GameMaker!” Fast, beautiful games full of juicy particle-spewing, camera-shaking excitement that easily stand next to any other game. This is NOT some pared down prototyping tool or a drag-and-drop toy for kids. 

Of course, to do any of that, you have to have an idea and you need to be prepared to write some code. I have a soft spot for TV gaming, so my plan started with building an arcade-style space-shooter for Amazon Fire TV that could be played with a Fire TV game controller – mostly because that’s what I have at home and this began as just a side project for myself.

As I thought about it more, I realized that the world deserves more fun games, and darn it, they deserve MY fun game. To allow as many customers as possible to experience the excitement of my game, it would really be great if it was also playable on Fire TV Stick…with only the remote control. And of course it needed GameCircle achievements and leaderboards. To top it all off, I thought, “Hey, why not support playing on a touch screen too.”

Now I really had a challenge worthy of my long commute.

Over the next few parts, I’ll get into the hard-won details of how I built the remote and controller support, as well as GameCircle features in GameMaker: Studio, complete with sample code you can use in your own projects.

Don't miss the rest of the Building Retroids with GameMaker blog series!

Part 2: Basic Controller Detection

Part 3: Handling Controllers