Why Use Kotlin Over Java for Android App Development


A few years ago, when developers were questioned about which programming language they would prefer to develop an Android application, you would only get one answer: Java. But now, approximately 66% of the developers use Kotlin to build Android apps.

Java was the king long ago and was the most dominant language ruling the Android application development industry. Several popular applications, including Netflix, Spotify, LinkedIn, and Amazon, are built using Java.

However, with technology reaching new heights with each passing day, developers constantly search for newer frameworks that can efficiently support Android application development. In addition, they are looking for a framework that is more functional, powerful, and easy to use. As a result, Java became less popular and obsolete, and Kotlin emerged as the new framework.

Java is still the most proficient programming language, yet Kotlin is constantly growing with its short and multifaceted feature development tools. Did you know that Kotlin has been ranked as top 15 programming languages despite being just five years old?

There is no better alternative than Kotlin to build smart, user-friendly, and progressive applications similar to the existing ones.

What is Kotlin?

It is an inactively captured free, open-source (FOS) programming language that JetBrains developed. Kotlin offers a brief code composition that makes it one of the most dominant picks for Android mobile application developers.

It is assembled to JavaScript or native cryptogram and generates code to build on the Java Virtual Machine (JVM), Android, JavaScript, and Native. Kotlin is used by 8.32% of developers across the globe. The major benefits of using Kotlin for mobile app development are:

  • Simpler to read code.
  • Less effusive.
  • A brief set of libraries.
  • Informal refactoring.
  • Quicker assembling time.

Significant Features

Kotlin is efficient in that it codes your mobile app easily as the syntax is intuitive and lean.

Kotlin allows you to enhance additional features to your prevailing application, making it simple for you to complement modest yet inspiring features.

Kotlin certifies that each phenomenon works as a non-null, dipping the number of clatters at runtime.


There are plenty of advantages to picking Kotlin over other programming languages. First, Kotlin is a contemporary programming language without too much obsolete gear. This means there are fewer flukes and reduced perplexing features.

It is an accumulated language, and you will have an easier time ascending your application to various platforms or devices, even to mobile applications written in Java. Some of the other advantages of developing mobile app using Kotlin are:

  • Reliable
  • Make the best use of the productivity
  • Easy to learn
  • Works with standing java code
  • It can be easily maintained
  • Less buggy
  • Null safety and lambdas
  • Merges functional programming
  • Merges procedural programming


Kotlin is considered to be a great programming language to develop Android applications. It is briefer and type-safer than Java. But there are some disadvantages of utilizing Kotlin as your prime mobile app development programming language.

Kotlin is supported on new devices for a specific time and can be difficult to debug. It has had affinity problems with older Android versions and the tackles used for building Android applications. The most common disadvantages of developing mobile apps using Kotlin are:

  • Kotlin has minimal learning opportunities
  • Different from Java
  • Difficult to debug
  • Compilation speed
  • Fewer Kotlin professionals
  • Limited sources to learn

What is Java?

Java is the most common multipurpose object-oriented programming language (OOP language) used for developing android applications. It is used by 35.35% of developers across the globe. Java is also used to build desktop and web applications. In addition, it is a platform-autonomous universal language used for programming. Therefore, it has been a prevalent choice of language in several enterprises for decades.

Most organizations have implemented it owing to its permanence. As a result, approximately 15 billion devices are using Java.

Java is popular due to its simplicity and availability of resources. Moreover, it is simple to get started with Java because it is one of the most commonly used mobile app development programming languages.

Significant Features

  • Java is a multi-pattern, feature-rich, inferred, and dominant programming language that provides great efficiency for developers.
  • Due to its regressive compatibility, Java is a substantial enterprise application necessity.
  • Consistent updates make Java the number one choice of developers.
  • The runtime of Java Virtual Machine (JVM) is the best among Virtual Machines in the Information Technology business.


Java is the best choice for mobile app developers looking to work with Android app development. Along with Kotlin, Java offers the best affinity for applications on Android devices. If you plan to release your application on the Play Store, you must ensure that it is well-suited to all mobile devices.

Some other advantages of the Java programming language are:

  • Simple
  • Object-oriented.
  • Automatic garbage collection.
  • Cheap and economical to maintain.
  • High-level programming language.
  • Secure language
  • Robust and stable.
  • Platform independent.
  • Supports portability features
  • Supports multithreading
  • Efficient memory allocation strategy.


Despite being one of the most prevalent mobile application development programming languages globally, Java has many disadvantages. The major problem is that Java is hard to learn and entails years of practice to be effective. It also provides many libraries, which makes it tough to acquire.

Some other disadvantages of the Java programming language are:

  • Accessibility of templates.
  • Costly memory supervision
  • Sluggish is equated to other languages like c and c++.
  • Poor and slow performance.
  • Unattractive look and feel of GUI
  • No backup facility.
  • Complex codes.

Popular Apps Built on Kotlin

Some of the most popular applications built on Kotlin are:

  • Google
  • Pinterest
  • Square
  • Trello
  • Evernote
  • Slack
  • Corda
  • Uber
  • Coursera
  • Netflix
  • Airbnb
  • Basecamp

Popular Apps Built on Java

Some of the most popular applications built on Java are:

  • Netflix
  • Spotify
  • Amazon
  • Twitter
  • LinkedIn
  • Opera Mini
  • Nimbuzz Messenger
  • CashApp
  • ThinkFree Office
  • Signal
  • Murex
  • NASA WorldWind

The Difference between Kotlin and Java

Java is a multipurpose object-oriented programming language, and together with JavaScript HTML and Python, it is amongst the most common and widely used programming languages globally. Kotlin is still far away from being on that list, but it has been a threatening competitor in the field of Android development.

One year after it was announced, in 2017, Google documented Kotlin as their subsequent certified language for Android development. In 2019, Google recognized Kotlin as the preferred programming language for Android apps. As a result, the Kotlin programming language experienced remarkable growth.

Let us look at a few differences between Kotlin and Java:

1. Null Safety

Kotlin - In Kotlin, it is impossible to feature null values to variables or gadgets consequently.

Java - NullPointerExceptions in Java allow app developers to feature a null value to any variable or gadgets consequently.

2. Extension Functions

Kotlin - Kotlin enables app developers to spread the capability of classes without essentially having to receive from a class.

Java - To spread the capability of a prevailing class, one must develop a new class and accede to the fundamentals of the parent class.

3. Code

Kotlin - Characteristically entails less code and is a straightforward identical language.

Java - Necessitates more appearances of code than Kotlin.

4. Coroutines Provision

Kotlin - Offers coroutines provision. Coroutines are reckless and consent the developer to generate code, suspend the performance, and restart it again.

Java - Java allows the formation of several background threads when conducting extensive operations.

5.  Data Classes

Kotlin - Kotlin provides an additional upfront way to form classes to grip data by simply incorporating the "data'' keyword in the class description.

Java – The developers need to create the fields to accumulate the data, the constructor, and the getter and compositor outcomes for the variables and other purposes, such as the hash Code and generations.

6. Smart Casts

Kotlin - The brilliant casts attribute holds casting drafts. Kotlin's smart compiler repeatedly succeeds redundant casts.

Java - The developer must draft the variables' category following the action.

7. Checked Exceptions

Kotlin - Checked exceptions are unavailable on Kotlin. Therefore, Kotlin's developers do not need to catch or assert exclusions.

Java - Java developers, have checked the exclusions provision.

8. Efficient Programming

Kotlin - Kotlin is a combination of object-oriented and efficient program design. It can practice lambda terminologies and high-order roles.

Java - Java is more inadequate to the impression of object-oriented program design and cannot practice lambda technologies.

9. Primitive Categories

Kotlin - In Kotlin, once you start a variable of a primitive category, it will be automatically measured as an entity.

Java - In Java, variables of a primitive category are not entities; they are predetermined in Java's data categories.

10. Community Fields

Kotlin - Kotlin does not offer community fields.

Java - Community fields (commonly known as public fields) are accessible in Java.

11. Wildcard Categories

Kotlin - Kotlin does not offer wildcards.

Java - Java offers wildcards.

12. Implicit Alterations

Kotlin - Kotlin does not offer support for implicit wide alterations.

Java - Java supports implicit alterations, meaning the developers cannot execute explicit alterations.

Why Use Kotlin Over Java

Even with all the differences mentioned above, both the Java Android app and Kotlin Android app accumulate to p-code. Hence, developers can implement Kotlin code to Java and vice versa. As a result, this allows both programming languages to be used in the equivalent development plan.

Well, you may wonder why use Kotlin over Java? The answer is, Kotlin provides several benefits for Android app development, including:

  • Organized concurrency
  • Entails less coding
  • Interoperability
  • More Concise Than Java
  • Strong and Safe Coding
  • Efficient Compilers
  • Ease of Maintenance
  • Increased Productivity
  • Enhanced Performance
  • Nullability Issue Handling

In addition to providing numerous benefits over its competitor, Kotlin also addresses several weaknesses of Java programming languages:

1.   Conciseness

Globally, many developers admire Kotlin for being succinct. This is a value Java programing language is not acknowledged for. However, readability should constantly take significance over conciseness.

The concise nature of Kotlin eases a developer's work and alleviates the risk of mistakes, but Kotlin does not exercise conciseness for briefness's sake. Boilerplate code is tricky to develop and leads to additional bugs and lost time classifying and recognizing them.

2.   Interoperability

Interoperability is Kotlin's fundamental function. Its purpose has been to use general information and skill from the launch to brand all collections accessible to Kotlin programmers. As a result, developers can easily develop components in Kotlin that work perfectly within prevailing Java code. By releasing the p-code, a Kotlin compiler lets the two programming languages function in harmony in the same project.

3.   Built-in Null Safety

Kotlin's category classification has inherent null safety. The well-known NullPointerException is mainly accountable for Android application development errors. Android depends on null to characterize the nonappearance of a value, but null can effortlessly terminate an application.

Kotlin cracks this problem by integrating characteristic null protection. This accumulation protects developers from writing additional code to function around the issue.

4.   No Raw Categories

Before the invention of generics, basic categories were used quite often - basic categories consent to backward affinity. However, raw categories can heave a CastClassException, and the mistake will happen throughout implementation and not the compilation stage. Therefore, Kotlin does not allow raw categories, and as a consequence, generates a clear and safe code.

5.   No Checked Exceptions

The checked exception characteristics in Java are tricky and cause problems. Checked exceptions are when the accumulator cracks the denominator of a function to seize a lapse.

The fact is, checked exceptions are frequently redundant and source blank hold blocks. Furthermore, imaginary checked exceptions are frustrating for developers as blank hold blocks force developers to pick through the code to classify an imaginary exception.

As a solution, Kotlin eliminates checked exceptions completely, which reduces verbosity and progresses a safe code.

The Commercial Advantages of Switching to Kotlin

Rebuilding huge proportions of a project in an entirely different programming language could be a thoughtful and difficult choice. However, Kotlin provides two crucial commercial advantages that can influence the decision.

Minimized Project Timelines

Kotlin's conciseness assistances mean the programming language can crack more glitches with fewer lines of code. Kotlin's brevity nature lets developers write and adapt code more proficiently, minimizing a project's time.

Fewer Application Crashes

Kotlin apps use a lesser amount of coding in comparison with Java programs. Not only does writing less code minimize development time, but less coding also provisions preservation requirements.

There is a less external range for bugs to hide and the improved readability of the programming language makes positioning bugs simpler for developers, ensuing lesser crashes and system catastrophes.

The Future of Kotlin

The pros of Kotlin for Android app creators are indisputably the future of Android development. With massive enterprises switching to Kotlin from Java for official app development, support from Google, and an almost universal attachment to the programming language, it is quite safe to state that Kotlin will grow with time only.

Kotlin is rapidly demonstrating itself as the best programming language for mobile app development and offers developers plenty of chances to test contemporary program design. Globally, Kotlin is regulating a new example of what a program design language should be capable of achieving.


For Android app development, Kotlin appears to be the better choice at the moment. This is because many enterprises and developers are implementing it, and the future of the Kotlin Android language seems to be growing rapidly.

However, Java remains an exceptional multipurpose object-oriented programming language. Additionally, it has been preferred for Android for a long time, so it is difficult to wipe out Java completely and replace it.

Furthermore, there are several other characteristics to reflect on than only the differences in programming languages. These include the programming language enterprises have been using for a long time and the comfort level developers sense with Kotlin programming language or Java programming language.