The extension of the Android app is APK, all those who have sidloaded the app separately from the Play Store once are familiar with this format. Be it Play Store or Third Party App Store, APK format has been used for Android applications in most cases till now. But according to a recent decision of Google, we are going to replace the APK format with Google's proprietary format AAB. Google's decision has sparked widespread criticism. Google made the decision following the announcement of native Android app support on Windows 11. Many people think that this step is already for the future to limit Android App Support (Amazon Store) to Windows 11.
What is APK & AAB and how does it work? When is it going to be launched? Why this sudden move? What are the advantages and disadvantages of this, etc. will be the content of today's article. So let's get started-
APK vs AAB: Basic Concepts
APK and AAB are two very different formats. It's not that we see too many extension formats for pictures or multiple videos. Although the work of each extension format is the same, it does not have the same advantages and disadvantages. APK is an Android application format which is full of Android application package. In this APK, all the resources like code, layout image and video are given together to run an application. One thing to note here is that we have a lot of differences between different phones in the hands of different people. Such as: screen size, processor architecture, etc. So a universal app is made and published. But it turns out that a lot of specific users are not needed. For this reason, on the one hand, there is an increase in the storage of the phone, on the other hand, due to the high cost of internet bandwidth as well as having a lot of unnecessary resources, the app becomes bulky. Increased startup time causes a lot of problems, starting with the resource becoming hungry. Although it is possible to overcome this problem by publishing a few APKs, in most cases the developers have been seen bundling everything together while creating the app.
In August 2016, Google launched a new option for developers in the Play Store. That is AAB or Android App Bundle. Developers have since been able to select AAB as well as APK when submitting a new app to the Play Store. But AAB is not a universal packaging format like Google's own publishing format APK. In AAB, the developer has to submit all the resources to Google in AAB format. Google will then generate an APK from the bundle according to the user's location, phone requirements, which will be installed on the user's phone. As a result, startup delays will decrease and app speed will increase. Google claims that this format will reduce app size by at least 15%. In addition, AAB's Play Feature Delivery will allow you to download everything you need to open an app and run the app in the fastest time possible.
Developers can also enable specific features for specific devices if they wish. AAB's apps will be in the range of 150MB if additional data is required for twenty games it will be sent via Play Asset Delivery. You can find out more about Play Asset Delivery here. Many popular apps have already moved to AAB format. Among them are AirBnB, Netflix and many more including Twitter.
APK vs AAB: App Signature
Let's talk about app signature this time. App signing is very important for Android app security. App signing stops app tampering. When installing an app from the Play Store, if the third party wants to install the update from a store, then the app signature is matched and can be installed only if it matches. If the app is tempered with malware then the app signature will not match. App signatures, also known as "public keys", are generated from a "private signing key". These "keys" are provided by the developers and are publicly hidden. But since the app bundle will generate APK on Google, you have to give time to submit “Private Signing Key” as AAB. As a result, app signing will go far beyond the control of Google. The security of this "key" is stated by Google to be kept with other "keys" which are stored in a very high security database.
New decision on AAB
So, why is there so much fuss now about a format that was launched in 2016? The answer is, so far a developer has two options, APK and AAB, but next month, that is, from August, all the new apps that will be submitted to the Play Store will have to do in AAB format. For now, there is no obligation to bring the old apps in the Play Store under AAB.
While there are advantages to the AAB format, there are also some disadvantages for developers as well as for third party app stores. First, control of the "signing key" from developers to Google. Due to which there are many developers who publish the app simultaneously in the Play Store as well as in the third party app store (Amazon Store, Huawei AppGallery). There will be some extra work for them to go to the APK format separately for those stores and developers will have to update different versions for different stores. However, Google has said that developers can download the APK from the Play Console if they wish. AAB cannot be loaded as easily as APK can be loaded as Android package installs do not yet directly support AAB unpacking. If you want to load AAB side, you have to do it in different ways which is time consuming. Moreover, many app modded or cracked versions could be found, but it will gradually be discontinued. However, the use of APK / AAB will not affect the general users.