Difference Between an API and an SDK Anyone Can Understand

7 min readJul 20, 2021
Difference Between an API and an SDK Anyone Can Understand

To understand the difference between an API (Application Programming Interface) and SDK (Software Development Kit), you don’t need to be advanced in programming. In this article, we are going to unlock the definitions of APIs and SDKs, come up with case examples as well as draw a line of difference between the two.

What is an API?

What does an API mean? The API or the Application Programming Interface is what the term denotes — an interface.

What does it do? API allows the software to interact with other software. Suppose you have two different sets of languages. The API is like Google Translate between them. It allows these two languages to understand each other.

You use an API each time you interact with the computer. For example, when performing simple tasks, like copying and pasting or sending Facebook messages, you use an API.

Before, it was not so. The programmers had to code with elaborate codes and provide sets of commands and instructions. Today, APIs allow for consistent coding creating a more stable and predictable programming environment.

Modern APIs have sets of characteristics. For example, they are more developer-friendly. They are documented and standardized. They have their own software development lifecycle (SDLC) for the design of a computer product as well as for its management.

Examples and Use Case of APIs

APIs are used across a variety of industries, like healthcare, transportation, banks, and more.

Let’s take the example of Netflix which is so popular that you cannot miss all the nuances. What does Netflix do with APIs? Well, it has well-normalized APIs that serve metadata from movies, manages user requests, image service, and the actual streaming of data.

How does it work? Large-scale API-building is challenging especially when you have a bid domain and lots of clients need to get data from different bounded contexts. Netflix uniquely solved this issue.

At Netflix, they created middle-tier optimized servers that resemble the Backend for Frontend (BFF) pattern. What they do is that they are pushing some code to a client-optimized API server. In essence, the middle-tier server takes care of API calls from clients.

The example above shows that you don’t need to write time-consuming codes anymore. In other words, app development is super simplified with APIs. And if you need to grab one now, here is a list of Manufacturing APIs that you can easily integrate.

What is an SDK?

What does an SDK mean? SDK stands for software development kit or, simply put, devkit. It’s a set of tools and programs that are used to develop applications. The beauty of an SDK is that the developers don’t have to create applications from scratch. Functionalities like sending mobile notifications or gathering analytics data are all custom-coded. As a result, applications are developed much faster saving time and money for the customer.

Why would a developer need a devkit? They need it to create software. Would it be possible to create software without an SDK? The answer is ‘’yes’’. But with SDK, it’s much faster and more efficient. Not only can you create software for different platforms, like Android or iOS, but also you can also create apps that operate in different programming environments. Developers can use SDKs for websites, set-top boxes, and other digital platforms.

Examples and Use Case of SDKs

Here is a short list of free iOS apps with popular SDKs.

The iOS SDK is just one example of the many SDKs that are available for application development. Other examples of popular SDKs include the Java development kit (JDK), the Windows 7 SDK, the MacOs X SDK, and the iPhone SDK.

These are examples of SDK use cases:

  • Analytics and crash reporting
  • User Login/Authentication
  • Notifications, Engagement and Messaging
  • Advertising
  • Payments.

Let’s take the example of advertising and see how SDKs work in Ad Manager. Ad Manager uses the Google Mobile ads SDK. To generate revenue, the default integrations of this SDK collect data. For example, it may collect information on a device and display ads as a banner or a native ad.

To integrate and set up the SDK with your app, you need to download the Google Mobile ads (GMA). If you need help, use the Android or iOS quick start guides.

Difference of an API and an SDK in Plain Language

Broadly put, an API is an interface that allows software programs to interact with each other, whereas an SDK is a development tool for applications. It’s like a simple SDK but without the ability to create applications. Rather, it’s a connection line between these applications.

Think of an API as a library that provides access to applications or a piece of hardware. SDKs are much more elaborate. They contain a collection of tools like compilers, libraries, debuggers, IDEs that are used for application development.

In other words, an SDK is a complete package of tools whereas an API is just an interface to interact with. APIs are like words that you can use, and SDKs are like sentences that have been put together for you.

While searching for the difference between an API and SDK, I have found another very good analogy. The SDK is like an entire house with different rooms, furniture, telephone lines, etc., whereas an API is just the telephone lines that allow communication in and out of the house. In other words, an SDK contains an API but not vice versa.

Comparison of API vs SDK

Let’s look at an example again.

Take the travel industry. How can travel booking websites aggregate thousands of flights and show the cheapest option? The answer is that APIs allow machines to easily and automatically exchange data. Can you imagine how much time it would be needed for the hotel attendant to manually send emails to collect information about the availability? By the time the attendant collected all the information, it would be too late!

This example explains how APIs ensure communication between applications. They are the communication lines between different software.

Here is a good example of an SDK in use. Most mobile apps need login and authentication of users, for example, Facebook, Twitter, and Google. All these companies have their own SDKs that allow the developer to perform the functionality. If no SDKs were used, functionalities like login requests, authentication, analytics, and crash reporting wouldn’t be possible to implement.

In short, SDKs are used for developing software applications. APIs are used for communication with other service providers/applications/platforms. An API may be part of an SDK which is not true for the other way around.

Comparison between SDK and API:

Final Words

To sum up, APIs are like channels between different applications, while SDKs are tools for building software programs. An SDK contains an API as well as sample code, technical specifications, and tools whereas an API contains specifications and descriptions about functions.

I guess you are clear now about the difference between an API and an SDK. You know ‘’what does an API mean’’ and ‘’what does an SDK mean”. Now let’s get to the real world and search for a company that can help you develop a software application or provide communication between third-party applications or platforms.

Here is why we recommend choosing Addevice.

Addevice is a reputable mobile application development company that has an extensive portfolio behind its back. A good example of a success story is Gulfsip, an app that helps thousands of people to make audio and video calls in the Gulf region. Today it has over 1 million users in the Gulf region.

You can be the next business that will take your idea to a new level. Whether you need to develop, debug, test, or deploy an application, Addevice is a way to go. Don’t trust our words. See what others have to say at GoodFirms.

Drop us a note if you have an idea that needs to be shaped into a mobile application.




You’ve got vision and goals. We’ve got expertise and a solid process. Let’s work together and bring them to life. https://www.addevice.io