How Does an Android App Works? (Noob Friendly)

'Android' - One of the most famous smartphones' operating system. But what makes it so special? Is it simplicity? Or it's performance? Well, the answer is - It's millions of awesome applications! I mean who doesn't like trying a brand-new application on their smartphone? But how the heck does Android application works? Let's get it clear! 

Basic Structure

Every Android application is 'written' in Java programming language. Yes, an app is always written in a code. That's because smartphones cannot read or speak English (duh). They only understand programming languages like Java, C++.etc Most of the developers use Android Studio to compile various codes of applications. Android apps always end with '.apk' file extension. It stands for Android package. You can even extract i.e decompile an app using WinRAR. You can see that it contains different folders like - src, drawable, layout, Res, gen.etc In simple words, these are the basic components of an app. The most important files in an app are - AndroidManifest.xml, MainLayout.xml and Activity Class.

Ever got an error like - 'There is a problem parsing the package'? It's all "AndroidManifest.xml's" fault! As it defines the minimum Android version required by the application.

Installing & Running of an application

Whenever you install an Android app, the '.apk' file is extracted and it's necessary files get copied to the Android system. It also assigns a unique Linux user ID to each application. The user ID is unknown to the app. It's only visible to the system. It is used to give necessary permissions required by the app. 

After opening the app, it's activities, services.etc gets activated in the background we are able to see and interact with that particular application. Each app consists of a lot of activities such as push notification activity, data activities.etc

(Image Source: Howtogeek.com)

                                        

In the newer version of Android 6.0, applications require a special permission from the user to show notifications (which is great!) In this case, the push notification service is deactivated until we grant permission to show notifications.

Reading & Storing Data

By default, an Android application can read some basic system data. To read and write some special file data such as photos, documents it requires different permissions (which is generally accepted by us while installing the application). Some applications like - File managers can even erase user data. 

Many applications can run in the background. Even if you close an app from the recent app list, it's services and activities remain intact. They keep running in the background. Such apps are constantly fetching, reading and storing data on your smartphone. For example - Messenger app by Facebook. Its message service is always running in the background. Such app uses a lot of RAM. As a result, your device becomes slow.

Conclusion

Basically, an Android app is a file build with codes using Android SDK which always ends with '.apk' extension. It consists of different services and activities. It can run in the background, read, store and delete user data. It always requires permissions to run.

Keep in mind that I've not covered everything in detail. I've only tried to give you a simple idea of how an Android application works. Hope you have got a fair idea about the working of Android apps.

Related Post: How to Remove Ads from Notification Bar?

Liked the article? It would be really AWESOME if you share it with your friends.