Which One Should You Opt for Android App Development? Kotlin or Java

There is no doubt that Java enjoyed a superior position when it came to the programming language and was considered as one of the most important tools for the Android app development.

However, with the passage of time, the Android developers got various other options as the programming language. Some of these include C#, Lua, C/C++, JavaScript, Scala, and Clojure etc.

But there is one particular statically typed programming language that has hogged the limelight and even Google I/O is focusing on it. It is Kotlin which was developed by JetBrains. In fact, the Google I/O has announced at a conference that they would make Kotlin as an officially supportive language for developing the android apps.

Soon after this all crucial announcement, there was a spur and the experts began to debate over which is better Java or Kotlin. One of the advantages that Kotlin also offers is that you can successfully be complied and run on Java Virtual Machine (JVM). To be frank and honest, we are here to witness why Kotlin excels over Java by focusing on its pros and cons.

1. Kotlin Can be Learnt Easily in Comparison to Java

The first convenience that Kotlin offers to the aspirants of Android App Development is that it much easier to learn it in comparison to Java programming language. Anyone can learn this language and you don’t need any prior knowledge of mobile app development.

In addition to that, the programming language can be written in quick time. Plus, if you are familiar say with Java or C# coding, it will be icing on the cake. In fact, the developers of Kotlin did a commendable job by simplifying the language that even children can learn.

2. Gets Full Support from Android Studio

Also, the developers get extended support from Android Studio and they get aware of the adaptation tools. It is interesting to note that while working on a project with Kotlin language, the developer can also choose Java simultaneously without any second thoughts in mind.

kotlin android studio

Therefore, even the Java practitioners can easily understand Kotlin and implement the same while building apps.

3. Kotlin Offers the Best Approach for Programming

When an Android Developer opts for a programming approach, he may have various options at his disposal. At times, it becomes somewhat tricky to pick a particular programming paradigm as each one has its own pros and cons. Now, you don’t have to create any confusion and rely upon Kotlin that offers a well-balanced combination of functional and procedural programming.

Kotlin also offers extension functions that help to extend the competence of the class. The developers don’t have to follow the same traditions and decorative patterns, which in turn, helps to modify the class.

However, those who have used Java will know that they need to make use of the utility class by using the codes from java.util.Collections. These codes are very long and complex as well. It will take a lot of time as well. But when you have Kotlin, why take the alternative route? Better use it.

4. Kotlin Provides Precise and Reliable Codes

In the dual between the Java and Kotlin over the codes, the latter offers a more comfortable experience to the developers as the codes are more concise and compact. If you have to write less codes, it will mean there are less chances of bug creation.

On the other hand, Java is a programming language where the developers need to use long-winded words for the coding whereas, Kotlin uses less boilerplate code.

Kotlin is known for its code reliability. Often it has been observed that the developers face problems related to runtime errors, the syntax failing to release, not using the null pointers correctly etc. the developers should know that it is the null pointers that that helps in writing an appropriate code free from errors. And all these advantages are offered by Kotlin.

The compiler won’t permit to use variables that do not have assigned values. So, if you want to use the variable, then it is important to put a question mark towards the end. The job of the complier is then to monitor the nullable value whenever the code is written. Now, what is the benefit? It enhances the security of the generated code.

5. Controlling the Consistency of Data

Another big advantage that Kotlin offers over its competitor Java is control over the consistency of data. This has indeed come as a huge blessing for the Android developers because they do not have to take the pains of going for the manual command system to keep up data uniformity.

In fact, they have a couple of options to change it. The first method is to represent it via keyword ‘var’ and the second is applying the read-only option through the keyword ‘val’. It only keeps data consistent but also reduces the threats and chances of flaws if any.

However, in the case of Java, the keyword used is ‘final’, which is not very helpful for the app developers.

6. The Advantage of Higher-order Functions

Well, typically speaking the higher-order functions are specific languages that can accept other functions as arguments or return it as value. However, one of the prime reasons why they are needed is that they help in shortening the programs even if it is very complex and has a difficult logical structure. The codes can be written in a graceful manner.

On the contrary, this is something which remains absent in the Java. You are not getting the accessibility of these commands here. With Kotlin you also get the facility of lambda expressions in which the functions does not get announced in advance, but it gets a call from another function.

7. Kotlin Beats Java in Data Classes

Some of the other areas where probably the Kotlin excels over the Java is with respect to the data classes. To simply the fact, classes are actually the storage houses where the data is stored and it is often indicated through a prefix such as var or val. This also is time saving and the codes can be read much more easily.

8. Let’s Analyze Some Other Areas

Some other areas where Kotlin has proved its worth more than Java is introducing the co programs such as version 1.1. This has been a boon for the Android app developers it helps to develop an asynchronous code, important seamless operation of the app.

In Kotlin the developers also don’t have to work extra for manually blocking the threads because the compiler does this job independently. The cost of the co programs is also budget friendly which also reduces the cost of the project.

Where Does Kotlin Fail to Impress

O.k. so far we have been talking all positive about Kotlin and emphasizing on the point that it has proved to more than worthy for the Android app development. However, you know very well that every coin has two sides. So, therefore, it is essential to discuss some areas where Kotlin has not shown a positive intent:

  1. Kotlin is a programming language that takes extra runtime size and its standard library enhances the size of .apk. It means it can support a size of around 800 KB, but anything more you will have to wait. So, be prepared to spare more time while downloading.
  2. During the initial stages of development, the developer can find difficultly in decoding and reading the codes. The codes are written in smaller sizes and this where Java wins the game as each of the written codes here is clear and concise.
  3. Although Google has announced its support for Kotlin and it has also very strong support from Android Studio but still it does not receive any official assistance from the company. Google has not started promoting Kotlin. Even the Android Studio tends to become slower if it is fully complied. Here again, Java proves to be better.
  4. You must know that Kotlin is still new as a programming language and the number of Java users are more in comparison to it. It does not have the relative support such as blogs, articles, and video tutorials as people are still getting aware of it. However, since its popularity is enhancing, we will see more developers using Kotlin to develop Android Apps.
  5. Apps developed in Java programming language are more compact when compared to Kotlin.  Some apps need to be built on the complex coding process which is more applicable to Java. But Kotlin developers are working to overcome this issue.
  6. The apps can be built at a much faster rate using the Java language than Kotlin.


Well, it can be said that it was an interesting battle between the two most widely used programming languages for developing android apps. However, for the most part of the discussion, it was Kotlin who kept on outshining Java and that why it is been seen as the future replacement.

But the other side of the picture is that it is still new in the app development market and will take time until it gets further boost. Though Google is ready to support it but not officially; so there is little help you will receive from that end.

Dhruv is Sr. Android Engineer at Mindinventory. He is passionate about Android and has got his hands dirty and feets wet with all things Android. He loves to explore the bleeding edge tech stuff. He is an early adopter and would like to stay up to date regarding latest trends in Industry.