SDK means software devkit or software development kit. Software devkit comprises a set of executable programs. These downloadable programs contain developer tools needed to create secure and stable mobile applications. The developer tools include app documentation, repositories, code examples, programming languages, guides, and processes. Developers integrate these functionalities into mobile apps.
These tools are platform-specific. For instance, to create an Android app, you require Android SDK. Whereas, an iOS app is created using an iOS SDK. Other types of SDK toolkits are VMware SDK and Nordic SDK for creating stable wireless or Bluetooth products.