WhatsApp is an instant messaging platform, designed to make communication quick and easy. It is designed for a mobile and web version - that means the conversations can be managed on multiple devices, a feature that is valued highly by users.It displays read and delivery confirmation, as well providing users with the option to create group chats and make voice calls. It is the world's most popular messaging app, with around 1.5 billion active users. It is available for Android and other smartphones absolutely free unless we are not exceed our daily data limit.Facebook Messenger is a standalone app operated ... Read More

WhatsApp and Telegram are called instant messaging platforms, designed to make communication quick and easy. Both apps are designed for a mobile and web version - that means the conversations can be managed on multiple devices, a feature that is valued highly by users.Both apps display read and delivery confirmation, as well providing users with the option to create group chats and make voice calls.DifferencesThe major differences between Telegram and WhatsApp are as follows −TelegramWhatsAppIt was launched in 2013It was launched in 2009In telegram we can do file sharing up to 1.5GBWhatsApp allows file sharing only 16MB.In one telegram group ... Read More

In this article, we will see how to find the number of repeated values in a Kotlin list.Example – Finding Repeated Values Using groupingBy()The Kotlin library provides an inline function called groupingBy() which creates a grouping source from an array to be used later with one of the group-and-fold operations using the specified keySelector function to extract a key from each element.The function declaration of groupingBy() looks like this −inline fun Array.groupingBy(    crossinline keySelector: (T) -> K ): GroupingIn this example, we will create a list of values and implement groupingBy() in the list.fun main(args: Array) {   ... Read More

A Mutable List is an interface and generic collection of elements. Once a collection is declared as mutable, it becomes dynamic and we can modify its data as per requirement. A mutable list grows automatically in size as we insert new elements into it. The Mutable List inherits form the Generic class.Example – Creating a Mutable List in KotlinIn order to create a mutable list of repeating elements, we will be using Kotlin List(). By definition, it looks like this−inline fun List(    size: Int,    init: (index: Int) -> T ): ListAs we pass an initial default value, ... Read More

The concept of exception in Kotlin is very much same as it is in Java. All the exceptions in Kotlin are the descendants of the Throwable class. @Throws annotation indicates what exceptions should be declared by a function when compiled to a JVM method.Example – Throwing exception using a methodIn this example, we will create a scenario where we will generate a logical arithmetic exception, but we will try to throw a different exception using the @throws annotation and a function call.import java.io.* import kotlin.jvm.Throws fun main(args: Array) {    val item=0    var result=0    try {   ... Read More

List denotes a List collection of generic data type. By , we understand that the List does not have any specific data type. Let's check how we can initialize such a collection in Kotlin.List can be of two types: immutable and mutable. We will see two different implementations of initializing List.Example – Initialize List ~ Immutable ListOnce a list is declared as Immutable, then it becomes read-only.fun main(args: Array) {    var myImmutableList = listOf(1, 2, 3)    // Convert array into mutableList    // Then, add elements into it.    myImmutableList.toMutableList().add(4)    // myImmutableList is not a ... Read More

A Map is a collection where data is stored as a key-value pair and the corresponding keys have to be unique. A HashMap is a collection class based on MutableMap interface and it does that by implementing the MutableMap interface of HashTable.Kotlin provides four types of constructors to define and manipulate a HashMap.Example – Map Creation and Iteration in KotlinIn this example, we will be creating a Map called "subject" and we will be iterating through it.fun main(args: Array) {    // Declare HashMap    var subject : HashMap       = HashMap ();    // Assigning ... Read More

In order to remove extra whitespaces in a string, we will use the replace() function along with toRegex() function from the String class. To replace all the consecutive whitespaces with a single space " ", use the replace() function with the regular expression "\s+" which matches with one or more whitespace characters.Example – Removing extra whitespaces in KotlinTake a look at the following example −fun main(args: Array) {    var myString = "Removing ex tra spa ce from String"    println("Input String: " + myString)    // removing duplicate whitespace    println("Extra whitespaces removed: "    + myString.replace("\s+".toRegex(), " ... Read More

Kotlin provides a set of bitwise operators that we can use on integers. These operators can be applied only to Int and Long type variables. Here is the list of bitwise operations available in Kotlin −shl(bits) – Signed Shift leftshr(bits) – Signed shift rightushr(bits) – Unsigned shift rightand(bits) – Bitwise AND operatoror(bits) – Bitwise OR operatorxor(bits) – Bitwise XORinv() – Bitwise inversionKotlin does have functions for each of them.Example: Bitwise Operators in KotlinThe following example shows how you can implement the bitwise operators in Kotlin.import java.lang.* fun main(args: Array) {    val value = 5    println("Input value: " + ... Read More

return@ is a statement in Kotlin which helps the developers to return a function to the called function. In simple words, return@ can return any value, anonymous function, simple inline function, or a lambda function.Example – return in Kotlinfun main(args: Array) {    val s = message()    println("Message = $s") } fun message():String{    return "Hello Kotlin! This is a returned message." }OutputIt will produce the following output −Message = Hello Kotlin! This is a returned message.Example – Kotlin Labeled returnNow "return@" helps to control the flow to a specific level inside the code. In Kotlin terminology, it is ... Read More