Android App Development

Mastering Android App Development demands a harmonious blend of advanced technology and flawless user experience design.

What is the Android?

By now, most people know there are two major mobile operating systems: Google’s Android and Apple’s iOS. There used to be a lot more, but now pretty much every major mobile device runs one or the other.

Android is a software package and linux based operating system for mobile devices such as tablet computers and smartphones.

It is developed by Google and later the OHA (Open Handset Alliance). Java language is mainly used to write the android code even though other languages can be used.

The first beta version of the Android Software Development Kit (SDK) was released by Google in 2007 where as the first commercial version, Android 1.0, was released in September 2008.

The source code for Android is available under free and open source software licenses.

colors.xml
colors.xml file contains color resources of the Android application. Different color values are identified by a unique name that can be used in the Android application program.
strings.xml
The strings.xml file contains string resources of the Android application. The different string value is identified by a unique name that can be used in the Android application program. This file also stores string array by using XML language.
styles.xml
The styles.xml file contains resources of the theme style in the Android application. This file is written in XML language.

Android Application File Structure

It is very important to know about the basics of Android Studio’s file structure.

AndroidManifest.xml
Every project in Android includes a manifest file, which is AndroidManifest.xml, stored in the root directory of its project hierarchy. The manifest file is an important part of our app because it defines the structure and metadata of our application, its components, and its requirements.
Java
The Java folder contains the Java source code files. These files are used as a controller for controlled UI (Layout file).
drawable
Drawables may take a variety of file like Bitmap (PNG, JPEG), Nine Patch, Vector (XML), Shape, Layers, States, Levels, and Scale.
layout
A layout defines the visual structure for a user interface, such as the UI for an Android application. This folder stores Layout files that are written in XML language.
mipmap
Mipmap folder contains the Image Asset file that can be used in Android Studio application. You can generate the following icon types like Launcher icons, Action bar and tab icons, and Notification icons.
build.gradle(Module: app)
This defines the module-specific build configurations. Here you can add dependencies what you need in your Android application.

colors.xml
colors.xml file contains color resources of the Android application. Different color values are identified by a unique name that can be used in the Android application program.
strings.xml
The strings.xml file contains string resources of the Android application. The different string value is identified by a unique name that can be used in the Android application program. This file also stores string array by using XML language.
styles.xml
The styles.xml file contains resources of the theme style in the Android application. This file is written in XML language.

History of Android

The story of Android dates back to 2003 when Andy Rubin, Rich Miner, Nick Sears, and Chris White co-founded a start-up Android Inc. in Palo Alto, California. However, the company was later faced with the insufficiency of funds which brought Google into the picture.

All the four Co-founders soon moved to the Googleplex to continue to develop the OS further under their new owners. The first public Android Beta Version 1.0 was finally published on 5th November 2007.

Version	SDK / API level	Codename	Year
Android 15	Level 35	Vanilla Ice Cream	-
Android 14	Level 34	Upside Down Cake	2023
Android 13	Level 33	Tiramisu	2022
Android 12	Level 32	Snow Cone	2021
Android 12	Level 31	Snow Cone	2021
Android 11	Level 30	Red Velvet Cake	2020
Android 10	Level 29	Quince Tart	2019
Android 9	Level 28	Pie	2018
Android 8	Level 27 (Android 8.1)	Oreo	2017
Android 8	Level 26 (Android 8.0)	Oreo	2017
Android 7	Level 25 (Android 7.1)	Nougat	2016
Android 7	Level 24 (Android 7.0)	Nougat	2016
Android 6	Level 23	Marshmallow	2015
Android 5	Level 22 (Android 5.1)	Lollipop	2015
Android 5	Level 21 (Android 5.0)	Lollipop	2014
Android 4	Level 20 (Android 4.4W)	KitKat	2014
Android 4	Level 19 (Android 4.4)	KitKat	2013
Android 4	Level 18 (Android 4.3)	Jelly Bean	2013
Android 4	Level 17 (Android 4.2)	Jelly Bean	2012
Android 4	Level 16 (Android 4.1)	Jelly Bean	2012
Android 4	Level 15 (Android 4.0.3 - 4.0.4)	Ice Cream Sandwich	2011
Android 4	Level 14 (Android 4.0.1 - 4.0.2)	Ice Cream Sandwich	2011
Android 3	Level 13 (Android 3.2)	Honeycomb	2011
Android 4	Level 12 (Android 3.1)	Honeycomb	2011
Android 4	Level 11 (Android 3.0)	Honeycomb	2011
Android 2	Level 11 (Android 3.0)	Honeycomb	2011
Android 2	Level 10 (Android 2.3.3 - 2.3.7)	Gingerbread	2011
Android 2	Level 9 (Android 2.3.0 - 2.3.2)	Gingerbread	2011
Android 2	Level 8 (Android 2.2)	Froyo	2011
Android 2	Level 7 (Android 2.1)	Eclair	2011
Android 2	Level 6 (Android 2.0.1)	Eclair	2009
Android 2	Level 5 (Android 2.0)	Eclair	2009
Android 1	Level 5 (Android 2.0)	Eclair	2009
Android 1	Level 4 (Android 1.6)	Donut	2009
Android 1	Level 3 (Android 1.5)	Cupcake	2009
Android 1	Level 2 (Android 1.1)	Petit Four	2009
Android 1	Level 1 (Android 1.0)	None	2009

Advantages of Android

Android Is More Customizable Can change almost anything.
Android is Open-source. It means no license, distribution and development fee.
Android uses a highly optimized virtual machine for mobile devices, called DVM (Dalvik Virtual Machine).
Android OS is also available for televisions called Android TV.
Google’s been working hard to make Android’s user interface (UI) as flexible and customizable as possible.
Supports cloud storage enabling sync of devices with G-account.
Android gives users the freedom to download 3rd party widgets and also display their content on the home screen.
One of the biggest advantages of using devices running on Android platform is that it supports expandable memory.
Android phones can run many applications, it means you can browse, Facebook while listened to the song.
Android Developers SDK, Android Studio IDE, compilers, debuggers, emulators and all the other toolchains that you might need for a low-level development, testing and debugging.
Another point in favor of Android is the availability of millions of Android apps that you can install on the device from the Google Play store and other alternative stores.

Disadvantages of Android

Android requires the usage of Google account, most especially in installing applications, downloading content, or other activities you do—it needs to be backed up by your Google account.
Another thing that annoys users is the popup advertisements on Android, most especially on low-cost ones.
If you are running an old android smartphone, then you cannot update your smartphone to a newer version of Android.
When Google detects some issues with your software, it would be very permissive and might cancel your developer profile.
Android isn’t effective at protecting the infection. Users can import and install software from other foreign sites,.
Android doesn’t come with default virus protection like Apple devices but, users need to download anti-virus systems to protect the device from getting affected.
In the earlier system of Android, many applications still operate in the background but also move to the forefront as they would like.