Android Automotive OS is getting more recognition as automotive companies are looking to provide their customers with a more tailored experience. Here we share our guide to building the first app for AAOS.

Before you start,  read our first article about AAOS and get to know our review to be aware of what to expect. Let’s try making a simple  Hello World app for android automotive. To get an IDE, go to  Android Studio Preview | Android Developers and get a canary build:

In the next step, prepare SDK, check and download the Automotive system image in SDK manager. You can get any from api32, Android 9, or Android 10, but I do not recommend the newest one as it is very laggy and crashes a lot right now. There are also Volvo and Polestar images.

For those you need to add links to SDK Update Sites:

 https://developer.volvocars.com/sdk/volvo-sys-img.xml

 https://developer.polestar.com/sdk/polestar2-sys-img.xml

Start a new project, go to  File> New Project and choose  automotive with  no activity

A nice and clean project should be created, without any classes: Go to  build.gradle and add the car app library into dependencies, refresh the project to make it get

our new dependency:

implementation "androidx.car.app:app-automotive:1.2.0-rc01"

Let's write some code, first our screen class. Name it as you want and make it extend Screen class from  android.car.app package and make it implement required methods:

public class GrapeAppScreen extends Screen {



  public GrapeAppScreen(@NonNull CarContext carContext) {

      super(carContext);

  }



  @NonNull

  @Override

  public Template onGetTemplate() {

      Row row = new Row.Builder()

.setTitle("Thats our Grape App!").build();



      return new PaneTemplate.Builder(

              new Pane.Builder()

                      .addRow(row)

                      .build()

      ).setHeaderAction(Action.APP_ICON).build();

  }

}

That should create a simple screen with our icon and title, now create another class extending  CarAppService from the same package and as well make it implement the required methods. From  createHostValidator() method return a static one that allows all hostnames for the purpose of this tutorial and return brand new session with our screen in  onCreateSession() , pass  CarContext using  Session class  getCarContext() method:

public class GrapeAppService extends CarAppService {



  public GrapeAppService() {}



  @NonNull

  @Override

  public HostValidator createHostValidator() {

      return HostValidator.ALLOW_ALL_HOSTS_VALIDATOR;

  }



  @NonNull

@Override

public Session onCreateSession() {

  return new Session() {

      @Override

      @NonNull

      public Screen onCreateScreen(@Nullable Intent intent) {

          return new GrapeAppScreen(getCarContext());

      }

  };

}



}

Next, move to  AndroidManifest and add various features inside the main manifest tag:

<uses-feature

  android:name="android.hardware.type.automotive"

  android:required="true" />

<uses-feature

  android:name="android.software.car.templates_host"

  android:required="true" />

<uses-feature

  android:name="android.hardware.wifi"

  android:required="false" />

<uses-feature

  android:name="android.hardware.screen.portrait"

  android:required="false" />

<uses-feature

  android:name="android.hardware.screen.landscape"

  android:required="false" />

Inside the Application tag add our service and activity, don’t forget  minCarApiLevel as lack of this will throw an exception on app start:

<application

  android:allowBackup="true"

  android:appCategory="audio"

  android:icon="@mipmap/ic_launcher"

  android:label="@string/app_name"

  android:roundIcon="@mipmap/ic_launcher_round"

  android:supportsRtl="true"

  android:theme="@style/Theme.GrapeApplication">



<meta-data android:name="androidx.car.app.minCarApiLevel"

  android:value="1"

/>



<service

      android:name="com.grapeup.grapeapplication.GrapeAppService"

      android:exported="true">

<intent-filter>

<action android:name="androidx.car.app.CarAppService" />

</intent-filter>

</service>



<activity

      android:name="androidx.car.app.activity.CarAppActivity"

      android:exported="true"

      android:label="GrapeApp Starter"

      android:launchMode="singleTask"

      android:theme="@android:style/Theme.DeviceDefault.NoActionBar">



<intent-filter>

<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />

</intent-filter>

<meta-data

          android:name="distractionOptimized"

          android:value="true" />

</activity>

</application>

Now we can upload our application to the device, verify that you have an automotive emulator created, use automotive configuration, and hit run. The app is run in Google Automotive App Host, so if it is your first application on this device, it may require you to get to the play store and get it.

That’s how it looks:

The last thing, we’ll add a navigation button that will pop a  Toast . Modify  onGetTemplate() in  Screen class, add  Action and  ActionStrip :

Action action = new Action.Builder()

      .setOnClickListener(

              () -> CarToast.makeText(getCarContext(), "Hello!", CarToast.LENGTH_SHORT).show())

      .setTitle("Say hi!")

      .build();



ActionStrip actionStrip = new

Add it to  PaneTemplate:

return new PaneTemplate.Builder(

      new Pane.Builder()

              .addRow(row)

              .build()

)       .setActionStrip(actionStrip)

      .setHeaderAction(Action.APP_ICON)

      .build();

That’s our HelloWorld app:

Now you have the HelloWorld example app up and running using Car App Library. It takes care of displaying and arranging everything on the screen for us. The only responsibility is to add screens and actions we would like to have(and a bit of configuration). Check the Car app library to explore more of what can be done with it, play around with creating your app, and definitely check our blog soon for more AAOS app creation content.

 Quite a new droid around. The operating system has been in the market for a while, still missing a lot, but it is out, already implemented in cars, and coming for more. Polestar and Volvo were the first to bring Android Automotive OS to their Polestar 2 and XC40 Recharge.

Other car manufacturers like PSA, Ford, Honda, GM, and more announced that they are going to bring Android Automotive OS to their cars or just hinted about cooperating with Google Mobile Services. Part of implementations coming with Google Automotive Services(GAS): Play Store, Google Maps, Google Assistant, another part without, own app stores, assistants. What's most interesting for now is to bring your application to the store.

Building apps for the Android Automotive Operating System

Creating an android app for automotive doesn't differ that much from mobile and is similar to android auto. Starting in an android studio, setting it up for canary releases to get the emulators. The first issue is that Android Automotive OS emulation needs an Intel CPU right now and doesn't support Apple M1 or AMD. Available emulators start on Android 9(Pie), with Google and a custom one for Polestar 2, Android 10(Q) also with Volvo, skinned to look like XC40 cockpit, Android 11 and freshly released Android 12(API 32) emulators are Google only. To get your hands on custom versions for Volvo or Polestar 2,  you need to add links to  SDK update sites .

Challenges with Google Automotive Services

Lack of documentation and communication

Diving into the details of development and Android Automotive Operating System in general, the main thing you are going to spot is a problem with documentation and communication with Google, as the Android Automotive car feels like it is lacking options and solutions.

Developers and mobile groups are complaining about it, some of them trying to establish a communication channel and get Google on the other side. Google is not providing a clear roadmap for AAOS, and it is risky or at least could be expensive to develop applications right now. Some parts of the Operating System code hint at certain features, but documentation is silent about them.

Limited options to improve AAOS user experience

 Automotive applications are run in a shell (Google Automotive App Host) similar to those for Android Auto, and they do not have Activity thus UI can't be changed. Apps are automatically rendered, and all of them look similar.

There is still an option to install a regular application through ADB, but this might sound easy only for an emulator. Options for app developers to brand their applications are very limited, actually it is just an app icon at the top side of the screen and a color of progress bars, like those showing how much of a podcast or song you listened to already.

Car manufacturers and automotive OEMs have more options to reflect their brand and style of an interior. They can customize colors, typography, layouts, and more. There is still a requirement to follow design patterns for automotive, and Google is providing a whole  design system page .

Mandatory review

Applications submitted to the store are mandatory for an additional review. Reviewers have to be able to perform a full check, logins, payments, etc., so they need to be provided with all required data and accounts. That adds additional uncertainty with innovation and going beyond what is expected, as the reviewer has to agree that our app meets the requirements.

Focus on an infotainment system

Right now, the documentation states that  supported categories for Android Automotive OS apps are focused on in-vehicle infotainment experience: Media, Navigation, Point of Interest, and Video. Compared to Android Auto, it is missing Messaging category and adds Video. Requirements are in place for all apps in general or specific categories and most of those requirements follow the principle to make the app very simple and not distract the driver.

How does it work? If you don't have a payment option set on your account, it should ask you to add it on another device. You can't ask a user to agree to recurring payments or purchase multiple items at once. It is not allowed even if you are not driving, and that appears to be inconsistent with the video app category. For example, it is not allowed to work at all during driving, but can display video normally when stopped.

Play Store right now presents a handful of applications, fairly easy to count all of them, most of them being  in-vehicle infotainment systems : media(music and podcasts) and navigation apps. Nothing is stated about mixing categories, and none of the existing apps seems to cover more than one category.

Sensor data

Android Automotive Operating System being an integral part of the car, brings ideas about controlling features of a car, or at least reading them and reacting within an application accordingly. Emulation provides just a few options to simulate car state, ignition, speed, gear, parking brake, low fuel level, night mode, and environment sensors(temperature, pressure, etc.). There is an option to load a recording of sensor reads.

There are definitely more sensors that we are missing here that could have come in handy, and there is an extensive list of vehicle property ids to be read, with possible extensions from a car manufacturer and an option to subscribe for a callback informing us that property changed.

Managing car features

Coming to controlling a car's features leaves us with scarce information. The first thing that came to my mind was getting all the permissions through ADB, and it brought joy when permissions like car climate change appeared, but no service or anything is provided to control those features. Documentation reveals that there is a superuser responsible for running OEM apps that are controlling e.g. air-conditioning, but for now, there is no option for a dev to make your own app that will open a window for you.

The infotainment system should be possible to make and bring all the information you can get on a car screen(worth mentioning Android Automotive Operating System should be able to control the display behind the steering wheel, that is missed in documentation as well), but do not forget that there is no such category and possibly won't get through mandatory check.

What to look forward to in the upcoming future

After all, AAOS is here to standardize what we will see in our cars. It brings our most used applications, without plugging in the phone. We can choose our favorite navigation application and make shortcut icons for the most visited places. Our vehicle will remember where we were with our podcast and what playlist was on.

Looks like the system releases are becoming more frequent, Google is adding features that are necessary to control everything correctly from different cars. We should see it in more and more cars as this cuts costs for manufacturers and saves on developing applications. Custom skins and customizations for the screens can bring a bit of your style to your car.

Android Automotive Operating System summed up

That summary of what is going on in Automotive Android Operating System and Google Automotive Services might show there is a slight mess, both around code and documentation. That seems to be the feeling of most of the devs sharing their experiences. It is risky to develop apps without having a clear understanding of which way is the new droid going and without any board or support medium, at least to gather developers together.

That being said, it is a great time to put your app in the store and be there first. Explore what could get through the check and how far they let apps develop. We would love to get in the car at some point over a phone over an NFC spot and let it quickly adjust everything for you, with your key apps.

Do you want to start building apps for AAOS? Here is  our guide to help you create AAOS Hello World .

 Technology that allows vehicles to communicate wirelessly with other vehicles and road infrastructure is the go-to solution of the future. Regrettably, for the time being, the business justification for V2X roll-out by most OEMs remains beyond reach. What are the prospects for the coming years and what can be done to bring the vision of mass V2X implementation closer?

The role of V2X in supporting ADAS and AV

To begin with the basics, let's explore the dynamics of change today when it comes to automation in  the automotive industry .

The relationship between ADAS (i.e., the systems that currently prevail) and V2X (new type systems) is best captured in the chart below. It shows that the higher the SAE automation levels are, the more the role of V2X technology is emphasized.

Levels 0 to 2 represent the dominance of old-style, sensor-based security systems. Higher levels of automation are already more oriented toward extensive collaboration:

•  Between vehicles,
•  Between vehicles and infrastructure.

Advanced Driver Assistance Systems (ADAS) for the past 20 years have relied mainly on elements such as onboard sensors (cameras, radars, ultrasound). Low-level automation worked for a while, but it has its shortcomings. Primarily it is about its maximum range, which is only up to 200 meters. The other thing is its low performance in contact with obstacles, such as blind bends and densely parked vehicles.

Meanwhile, sensing technologies have developed so widely that today it is possible  to fully collaborate in such configurations as:

•  V2V – Vehicle-to-Vehicle.
•  V2D – Vehicle-to-device.
•  V2P – Vehicle-to-pedestrian.
•  V2H – Vehicle-to-home.
•  V2G – Vehicle-to-grid.
•  V2I – Vehicle-to-Infrastructure.

The most optimistic scenario assumes, among other things, that most  vehicles will be able to connect with each other on highways. And this will markedly increase road safety.

Does this mean that as automotive development continues, V2X will replace existing ADAS solutions? Not necessarily. Yet, it is possible that V2X will greatly expand the applications of current and future driver assistance systems. Thus, it will facilitate reaching  greater levels of vehicle autonomy.

V2X: benefits and unique selling points

V2X technology, which enables vehicle-to-vehicle and vehicle-to-infrastructure information exchange, is considered a resource worth having and developing in any automotive company. This is chiefly due to the numerous benefits that can be achieved in terms of traffic efficiency and safety. Here are just some of them.

•     Addressing the LoS       (Lack       of Sight)    problem which involves the non-visibility of another object. V2X can even detect elements that are invisible or undetectable by traditional sensors. This includes "blind spots" in the side mirror or objects behind a sharp bend.

•     Early warning.    Drivers of connected vehicles learn in a timely manner about dangers on multi-lane roads, especially high-speed roads. This allows them to react to the problem at an early stage. It is advisable to know that a vehicle's ABS system is activated within 1 mile of another vehicle equipped with V2X.

•     Reducing congestion and streamlining traffic.    With the technology described here, such modern fleet management methods as platooning can be successfully applied (see the following paragraphs for more details on this thread).

•  Driving assistance     even in adverse weather conditions.    Fog interferes with " standard" sensors, such as cameras. Meanwhile, the V2X also performs well during limited visibility.

•     Efficient alerting.    Approaching emergency vehicles can signal their presence from a great distance. Drivers are therefore able to quickly form an emergency lane on the highway.

•  Attaining higher levels of     vehicle autonomy.    Partially autonomous vehicles perform well in a wide range of scenarios on the road (including merging scenarios).

Are there any limitations when implementing V2X?

One of the obstacles facing OEMs at this point is insufficient demand. Although the technology is up and running and there are already many use cases around the world, consumers are reluctant to pay extra for it. This is happening for a good reason.

For example, most customers don't understand why they should pay extra for safety-related functionalities. These are already regulated by law anyway, and besides, they are guaranteed as part of ADAS (and these systems are already included in the basic vehicle price). Let's also bear in mind that a high level of data penetration in a car is not always possible. Most cars are still not high-tech enough. Many features would therefore simply be unavailable. So - why should we incur the cost of it anyway?

Beyond that, there is a long delay between the availability of the technology and the existence of a sufficient number of cars equipped with it. Meanwhile, to talk about V2X on a large scale, these two factors must exist in parallel.

Also, the road infrastructure is not necessarily designed to handle V2X. City authorities still have to focus on "putting out the current fires," so technological development sometimes takes a back seat. Besides, not all of the city's road investment is being carried out at the same time due to limited funds.

Of course, in the long run, safer roads and less congestion are the goal worth achieving, but things can't be done all at once. Examples from specific regions of the world, described in the following paragraphs, in fact, illustrate this point well.

DSRC vs. C-V2X

In the framework of V2X, there are two competing technology solutions:

DSRC - Dedicated Short-Range Communication

A form of wireless communication technology defined by the 802.11p standard. It is essentially an amendment to the IEEE 802.11 (WLAN) standard that defines changes and enhancements in order to effectively support Intelligent Transport Systems (ITS).

C-V2X - Cellular – V2X

A form of a wireless communication solution using mobile network technology. C-V2X has two modes of operation: PC5 (Direct communication) and Uu (Indirect method of communication using a cellular network).

Implementation of systems in specified regions of the world

After decades of development of the aforementioned technology, it is slowly becoming apparent that DSRC is giving way to the popularity of C-V2X. Although the former system still dominates in Europe and the US, this will certainly not last forever. According to experts, before long US and European OEMs will prefer C-V2X in their vehicles exclusively.  For the time being, however, both solutions are operating equally in these markets.

This is quite different from China, where the use of Cellular V2X has been embraced without question. For what it's worth, the issue is a bit more complicated in another Asian region, namely Japan, where DSRC-based ETC (electronic toll collection) has been under development for many years. In the Land of the Cherry Blossom, there is uncertainty about which way to eventually head. Cautious predictions, however, point to a slow transition to C-V2X.

Fundamentals for developing V2X

One thing to realize with V2X is that  the benefits are spread across all traffic users. For this to happen, however, some key driving forces are needed for the introduction and market adoption of this technology. These are:

1.     Platooning.  
2.     Fuel efficiency.  
3.     Smart cities.  
4.     Driver and pedestrian safety.  

•     Platooning  

Trucks moving in a single formation is an environmentally friendly and commercially viable solution. But what does it have in common with V2X? Quite a lot, because for platooning to take place, advanced communications technology is a must.

V2X allows trucks in a platoon  to coordinate braking and acceleration among each other. It also makes it possible  to perform many complex maneuvers .

    Main beneficiaries  

Carriers, fleet operators and the entire logistics industry, in general, would benefit enormously from V2X technology. This would not only optimize the transportation costs themselves but also fit in with increasingly stringent emissions standards.

•     Fuel efficiency  

Governments around the world strive to reduce their environmental impact by cutting emissions. In Europe, for instance, the EC Strategy on Sustainable and Smart Mobility is being prepared, outlining plans to reduce them by up to 90 (!) percent by 2050. To achieve this goal, policymakers are looking for technologies that help comply with the aforementioned limits. V2X shows huge potential in this regard.

Example? Solutions such as  GLOSA (green light speed optimization) minimize the need for a car to come to a complete stop just before traffic lights and then restart the engine or accelerate. Consequently, fuel consumption and harmful gas emissions are reduced.

    Main beneficiaries  

Environmental policymakers and regulators are (and will be) under mounting pressure related to emissions. V2X can play a key role in this puzzle, and it is up to policymakers to adopt and implement this technology.

The advantages of the aforementioned technology, however, can also be enjoyed by OEMs. Since V2X reduces fuel consumption, the driver spends less on a monthly basis. Such information can be quoted in marketing communications.

•     Smart cities  

The idea of a smart city is based on interconnected technologies and systems for collecting and using data. So it is quite natural that for functioning, smart cities need V2K solutions.

They enable communication between vehicles and buildings, signals, pedestrians, and other road users. All information is transmitted in real-time, so you gain greater awareness of your surroundings and current needs. More broadly, such intelligent transportation and road infrastructure management systems help reduce congestion. Noise levels, pollution in densely populated areas, and the likelihood of collisions are also curbed.

Automated urban logistics is the future of urbanization - without any doubt.

    Main beneficiaries  

Connected through VCX, a smart urban area can offer many benefits not only for overall security, but also for local commerce and the quality of life for its residents.

City authorities can plan individual processes more efficiently, resulting in real savings. In a potential scenario, city-funded traffic operators are immediately notified of incidents via V2X and smart cameras. By doing so, they warn other road users of the danger or make an instant decision to set up a detour. If necessary, they prioritize emergency vehicles.

Urban businesses are also enjoying the perks of a V2X-equipped smart city. That's because they benefit from shorter times for transporting goods from the place of manufacture to the point of trade. This is due to less congestion on the roads, intelligent route planning, and fully automated city logistics.

•     Driver and pedestrian safety  

Traffic collisions, injuries, and deaths not only incur unit costs but also seriously drain the public budget.

The solution to these problems may lie exactly in V2X technology, which makes it possible to identify more hazards on the road than ever before. Drivers can react more quickly to dangerous maneuvers by other road users and make early decisions that could potentially affect someone's health or life.

    Main beneficiaries  

Consumer purchasing power and public opinion certainly have a bearing on the success of V2X deployment. If road users understand that such solutions actually contribute to safety, they will be eager to push them.

Local politicians will also benefit from the achievements of new connected vehicle technologies. They, in fact, often base their election campaigns on claims related to reducing road accidents in their regions. And V2X is helping to fulfill those promises.

Who will implement first - cities or OEMs?

An important question to be answered is who will ultimately be responsible for the introduction and development of V2X. And who will begin to do it on a large scale.  The answer is not straightforward.

From the very outset, cities are faced with the difficult task of making significant infrastructure investments. For this, funds have to be obtained at some point, especially since once implemented solutions still have to be sustained. Certainly, though,  the benefits associated with V2X are well worth the funds expended on this technology.

On the other hand, we have OEMs that need a trigger to push their products forward. This must be fostered by the right market environment (a sufficient number of vehicles with V2X capabilities) and the commitment of the authorities responsible for maintaining public infrastructure. At this point, there are also constraints related to consumer reluctance, e.g. in the face of excessively high vehicle data penetration rates.

So, it all boils down to goodwill, openness to change, and the fact that certain technologies need to mature on the market.