Develop Android apps with Kotlin Use Kotlin to write better Android apps faster. Kotlin is a modern statically set type programming language that increases developer productivity and enhances developer productivity.

Jul 21, 2019

Modern and expressive

Kotlin’s modern language features let you focus on expressing your ideas and writing less boilerplate code. The less code you write, the less code you need to test and maintain.

Safer code

Use Kotlin to improve app quality. The @Nullable and @NonNull types are included in Kotlin’s type system to help you avoid NullPointerException. In addition, Kotlin has many other language features to help you avoid common programming errors.

Interoperable

You can call Java code in Kotlin code or call Kotlin code in Java code. Kotlin is fully interoperable with the Java programming language, so you can add as many Kotlin code to your project as you need.

Optimized for Kotlin

Kotlin is a production-ready language for Android application development.

Android Studio

Android Studio provides first-class support for Kotlin and even built-in tools to help you convert Java code into Kotlin code. With the Show Kotlin Bytecode tool, you can view equivalent Java code while learning Kotlin.

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Android KTX

Android KTX lets you take advantage of Kotlin language features to make Kotlin for Android development in a cleaner, more enjoyable, and more versatile way.

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SDK for Kotlin

Starting with Android 9 (API level 28), the Android SDK includes null comments to help avoid NullPointerExceptions. API reference documentation is also provided using Kotlin.

Note : Many Kotlin references are derived from Java-based source code. That is, some Kotlin references may contain Java code snippets.

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Learning Resources

Browse through a carefully selected set of resources to learn Kotlin quickly.

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What is the Kotlin code like?

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Kotlin training camp for programmers

Udacity courses created by Google to help you learn Kotlin quickly.

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Apps built with Kotlin

Many applications are built using Kotlin – from the most popular startups to the applications used by Fortune 500 companies.

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OWASP TOP !0

Injection. Injection flaws, such as SQL, NoSQL, OS, and LDAP injection, occur when untrusted data is sent to an interpreter as part of a command or query. The attacker’s hostile data can trick the interpreter into executing unintended commands or accessing data without proper authorization. Broken Authentication. Application functions related to authentication and session management are often implemented incorrectly, allowing attackers to compromise passwords, keys, or session tokens, or to exploit other implementation flaws to assume other users’ identities temporarily or permanently. Sensitive Data Exposure. Many web applications and APIs do not properly protect sensitive data, such as financial, healthcare, and PII. Attackers may steal or modify such weakly protected data to conduct credit card fraud, identity theft, or other crimes. Sensitive data may be compromised without extra protection, such as encryption at rest or in transit, and requires special precautions when exchanged with the browser. XML External Entities (XXE). Many older or poorly configured XML processors evaluate external entity references within XML documents. External entities can be used to disclose internal files using the file URI handler, internal file shares, internal port scanning, remote code execution, and denial of service attacks. Broken Access Control. Restrictions on what authenticated users are allowed to do are often not properly enforced. Attackers can exploit these flaws to access unauthorized functionality and/or data, such as access other users’ accounts, view sensitive files, modify other users’ data, change access rights, etc. Security Misconfiguration. Security misconfiguration is the most commonly seen issue. This is commonly a result of insecure default configurations, incomplete or ad hoc configurations, open cloud storage, misconfigured HTTP headers, and verbose error messages containing sensitive information. Not only must all operating systems, frameworks, libraries, and applications be securely configured, but they must be patched/upgraded in a timely fashion. Cross-Site Scripting XSS. XSS flaws occur whenever an application includes untrusted data in a new web page without proper validation or escaping, or updates an existing web page with user-supplied data using a browser API that can create HTML or JavaScript. XSS allows attackers to execute scripts in the victim’s browser which can hijack user sessions, deface web sites, or redirect the user to malicious sites. Insecure Deserialization. Insecure deserialization often leads to remote code execution. Even if deserialization flaws do not result in remote code execution, they can be used to perform attacks, including replay attacks, injection attacks, and privilege escalation attacks. Using Components with Known Vulnerabilities. Components, such as libraries, frameworks, and other software modules, run with the same privileges as the application. If a vulnerable component is exploited, such an attack can facilitate serious data loss or server takeover. Applications and APIs using components with known vulnerabilities may undermine application defenses and enable various attacks and impacts. Insufficient Logging & Monitoring. Insufficient logging and monitoring, coupled with missing or ineffective integration with incident response, allows attackers to further attack systems, maintain persistence, pivot to more systems, and tamper, extract, or destroy data. Most breach studies show time to detect a breach is over 200 days, typically detected by external parties rather than internal processes or monitoring.

Develop Android apps with Kotlin Use Kotlin to write better Android apps faster. Kotlin is a modern statically set type programming language that increases developer productivity and enhances developer productivity.

Modern and expressive

Safer code

Interoperable

Optimized for Kotlin

Android Studio

Android KTX

SDK for Kotlin

Learning Resources

What is the Kotlin code like?

Kotlin training camp for programmers