When talking about Android, libraries and frameworks are the ones helping developers to build apps more easily where several aspects (UI elements, debugging etc.) are well defined.
Such libraries offer detailed documentation, configuration data, templates, pre-built code and much more – all the developers need to get creative.
These are the libraries you should keep an eye on in the coming years.
The libraries to keep an eye on
Android Jetpack
Android Jetpack is a selection of software components which helps building reliable Android apps.
It provides a clear path for developers to build an Android app making it easier to support configuration changes and reduce boilerplate code and complexity with libraries that work across all devices and versions.
Problems like managing activity lifecycles or preventing memory leaks have been solved by AJ software components.
Jetpack consists of the androidx.* package libraries, unfolded from platform APIs, meaning it offers backward compatibility.
Since it gets updated frequently, you will always have the latest version.
Square/Moshi
Moshi JSON library, created by Square, converts JSON into Java and Kotlin models where converting JSON to Java model (and vice versa) is straightforward.
It’s a great choice for parsing JSON API responses in Android as it targets the Android platform, uses Kotlin features, it’s faster , it is lightweight with codegen and has a simpler API.
Moshi is better for you to handle any issues at the boundary of the data layer in your model, rather than reproducing them into the app and tracking them.
Kotlin’s native language features are supported by Moshi to ensure the type safety of a Kotlin class used with adapters to parse JSON responses.
Dagger
Dependency injection is a technique where an object receives other objects that it depends on.
When it comes to a good library for dependency injection, Dagger is a great choice.
It is a framework allowing developers to generate plain Java code. Its compile-time estimation proved very useful with challenges of large applications maintaining dependency injections.
Its advantage is that it uses compile-time for evaluating all the dependencies but you will have to tackle a demanding learning curve.
Nonetheless, Dagger flexibility will pay off in the long run.

Glide
Dealing with images on Android platform can get very difficult as its API is not optimised for smooth performance.
That is where Glide comes in – it is a fast image loading library for Android focusing on smooth scrolling. It’s an open source library which includes a flexible API with extensive decoding pipelines and automatic resource pooling.
Glide helps with fetching, decoding and displaying video stills, images or animated GIFs. (media and image files)
Glide uses HttpUrlConnection based stack that includes a versatile API to help developers to connect to almost any network stack.

Retrofit
Retrofit is the most used in Android development and it represents a type-safe HTTP client for Android and Java.
The library allows developers to define the REST API to incorporate different types of API calls.
You can easily manage API’s request body, endpoints and headers, add a query parameters and more via annotations, which makes everything clean and simple.
Retrofit is easy-to-use and offers a separate Rx module so it can work well with RxJava as well – such Rx module returns your API call like an Observable so you can chain it with the rest of your app.
Android DataBinding
Data Binding library is a support library allowing you to bind UI elements in your layout to data sources in your app via declarative format rather than using programs.
Android Databinding library is a view-binding library that achieves its results without use of annotations.
Code is shorter and easier to read while data and views are clearly separated. You get type safety for accessing views meaning that the compiler validates types while compiling and reports an error if you try to assign the wrong type to a variable.
It significantly reduces the amount of code written to access views, easy to set up and offers more functionalities.
RxJava
The best library in Android for reactive programming is RxJava. RxJava is an open source implementation of ReactiveX library for Java Virtual Machine (JVM).
Reactive programming is a huge help to developers so that the app can manage the changes automatically – it refers to event driven programming where data streams come in asynchronous way and get processed as they arrive.
RxJava enables developers to efficiently coordinate multiple actions simultaneously without using call backs or different actions triggered due to specific events in the system.
Besides simplifying Android app development, RxJava supports several JVM-based programming languages, implements stream abstracts through Three Core Constructs, simplifies multithreading through Schedulers and is compatible with several third-party libraries.
Room
Room is an official Android ORM – it relies a lot on annotations and standard SQL syntax while its APi is similar to Retrofit API.
The main benefit of Room over other ORMs is simplicity. While other ORMs come with more complex APIs, Room is incredibly easy to understand thanks to its standard SQL syntax.
Room also supports the Rx library and both of those libraries work together well.
Room is a good choice as it can be used without too much effort or time on your side in understanding its documentation.

Espresso
Mobile automation testing is a challenging task – Google developed Espresso framework to make this process easier.
Espresso is a testing framework library allowing you to create and develop UI tests for Android mobile apps.
Espresso provides a consistent and flexible API for automation of UI tests in an Android mobile app and the tests can be written in both Java and Kotlin.
You can easily conduct Android UI tests without the ramification of multithreaded testing.
Features supported by Espresso are simple API, providing separate modules to test and validate Android WebView elements as well as mock Android Intents – providing automatic synchronization between your apps and tests.
Advantages of Espresso are backward compatibility, it is easy to set up and has a highly stable test cycle while supporting testing activities outside the app as well.
The testing framework runs on Android devices and testing emulators creating a similar testing experience like end users have. If you want to use this library, you have to add dependencies to the app module.
Robolectric
Robolectric is a great library for unit testing and handling several aspects of Android apps including views, resource loading and more.
It can debug the Android mobile app against inflation or resource loading, view and other elements – it provides a way to run tests inside Android Studio without launching an app on device or Emulator.
You can grasp its capacity when reproducing a resilient testing environment where real devices can be tested for Android framework dependency performances.
It comes with robust scripts for thorough testing of the app functions via real devices and at the same time, other Android framework dependencies continue to work in the background.
Robolectric provides simulation of the Android SDK for carrying tests and it helps in preventing the need to use separate mocking frameworks.
How to Choose the Right Library?

No matter if you need an image library, a unit testing library or any other library, you should assess the information to make the choice easier for you.
Consider the following when choosing the right library:
Popularity
Check the ratings of the candidate library and how many or how severe are the issues reported for that library – usually, if the majority of developers like it, it can be a good indicator of quality.
Source Reliability
Do a check up on the author to minimize the risks to get a low-quality library. Check if they are active on Github or if released multiple libraries and try to verify your findings.
Well-structured Code
Go through the code to check if it’s well-structured – ensure that README files within are comprehensive and up-to-date for smoother and easier integrations.
Valid Licence
Licence is another factor to impact your decision because the usage of libraries can be limited. Make sure to follow all the terms of a specific library that you want to integrate into your app.
Open Source Quality
Access the library’s code to review its quality or performance – if you notice lack of transparency, it could signal a security risk.
Library Recommendations
Most platforms have several existing libraries and the best thing about it is that they are well-maintained and documented. Such libraries ensure low-risk but do your own research to understand their features, limitations and benefits.
Check Core Features
Do not strive to have full control over the code – libraries can cover a wide aspect of use cases. You cannot compromise on the performance, so rely on the actual tested libraries.
Conclusion
We chose all described libraries on the basis of their popularity among the Android community and the way our Android experts recommend them for different development needs.
These libraries in many ways represent the best of choices for every functional need in an Android project.