Developer Tools of the Trade: What Are SDKs?

What is an SDK?

SDK stands for “software development kit” and refers to a collection of resources that help developers build on specific operating systems (OSs) or hardware devices. A provider’s SDK includes everything a developer needs to start writing code for their app.  

There are countless SDKs available to developers, each with specific parameters for their platform. For instance, the Android SDK only works on Android-compatible platforms, and the iOS SDK facilitates app building for Apple products. Microsoft also offers its widely used .NET SDKs to developers interested in Windows OS.

If a developer wants to create an app for a specific platform, they’d first need to download the associated SDK. Although some SDK providers charge a fee, some offer it for free. 

Standard components of an SDK

Every SDK includes dozens of tools that help with coding, but not every package has the same components. However, here are some most common features of an SDK: 

1. Compiler: A compiler helps translate a high-level coding language like Java or C++ into a low-level binary code that a computer can use to execute commands. 
2. Debugger: A debugger scans a developer’s code to remove potential errors (i.e., bugs) before deploying an application. 
3. Libraries and code samples: Some SDKs include helpful instructions, examples, guides, or standard sequences to teach developers the best practices for coding on their platform. 
4. APIs: Short for application programming interface, an API is a bridge that helps different software applications exchange data. An SDK will include easy access to a platform’s APIs so developers can take advantage of external analytics, services, and features. 

API vs. SDK 

Remember, APIs are often included in SDKs. Although SDKs and APIs are separate, it’s common to confuse these two software tools. Indeed, the confusion between these services is so widespread that every intro to SDKs includes a section on “What is an API and an SDK?”

Think of an API as an invisible cable that connects one software application to another. APIs help different software apps talk to one another and exchange data. For example, if you google “weather in Orlando, Florida,” you’ll instantly see a snapshot of the current climate of the city. At the bottom of this weather snippet, you’ll notice that the data comes from Weather.com, which means Google uses the Weather Channel’s API to provide this information. 

As another example, it’s common for third-party businesses to use Google Maps’ APIs to list their physical location on a website. Google Maps offers both “Places” and “Routes” APIs to those interested in using Google Maps’ services on their apps. 

In the world of cryptocurrency, companies like CoinMarketCap offer APIs that provide real-time price feeds, volume charts, and other analytics on Bitcoin and altcoins. Many crypto investors also use the APIs in their centralized crypto exchange (CEX) accounts to share trading data on crypto tax software apps.

APIs are also crucial for communication in cloud computing. Clients who want to extract data from Amazon’s AWS, Microsoft’s Azure, or Google’s Cloud all use APIs for this task. 

While APIs are integral to inter-app communication, they don’t provide everything you need to build an application. APIs are just one component you can use while creating a new mobile app or desktop service. Therefore, an API will always be one aspect of an SDK. You need extra tools in an SDK to build an online application. 

Why are SDKs relevant? 

Without SDKs, developers would find it difficult to create the countless apps we use every day. While it would still be possible to develop without SDKs, these toolkits simplify the process of coding for various platforms. 

Computer programmers still need to master the basics of their preferred coding language, but they don’t need to be experts to create an app with an SDK. Since SDKs typically include guides and valuable samples, they make it easier for new developers to write clean codes.  

SDKs reduce the time, labor, and money developers need to build their online applications. These features streamline the app development process, which is excellent news for end users. 

From the platform’s perspective, SDKs are a powerful way to attract talented developers. Independent coders are more likely to use an interface that offers a simple-to-use SDK solution. Plus, since many SDKs are free, developers are more prone to give these toolkits a test run when creating products and services. 

How to use an SDK

Since SDKs are created keeping developers in mind, you’ll need a basic understanding of computer science and coding. You must also be familiar with whatever programming language corresponds with your SDK. For instance, Java is essential for coding on Android. And, if you’re interested in developing iOS applications, you should know about XCode, Swift, and Objective-C.

Once you feel comfortable writing in your target coding language, download an SDK and start exploring its features. Remember to verify that you’re using the official SDK associated with your platform. There are many malicious SDKs online that can corrupt data. Apple and Google have frequently removed apps from their stores due to malicious advertisement SDKs. 

SDKs and crypto: What’s the connection?

Blockchain SDKs work similarly to standard software SDKs. Developers still receive a set of tools like compilers, debuggers, and libraries when downloading a blockchain SDK. The primary difference is that blockchain SDKs are specific to Web3. Instead of building applications on centralized platforms like iOS or Android, a blockchain SDK gives programmers access to decentralized networks like Ethereum, Cosmos, and Tron.

While blockchain SDKs aren’t as widespread as those offered by Google, Microsoft, or Apple, they’re available to those interested in creating dApps (decentralized applications). A blockchain SDK provides developers the features required to create services in new sectors like DeFi (decentralized finance), play-to-earn gaming (P2E), and NFT (non-fungible token) trading. 

Blockchain SDK examples

While blockchain SDKs aren’t widespread in the software space, dApp developers have a few noteworthy options to streamline their operations: 

1. WorldID SDK: WorldID is a Worldcoin-developed protocol that enables developers to eliminate bots in their applications and ensure that humans only perform actions once. It leverages self-custody, Zero Knowledge Proofs (ZKPs), and credentials issued from devices such as Worldcoin Orb to provide this functionality in a privacy-preserving manner. 
2. Cosmos SDK: Cosmos is a proof-of-stake (PoS) crypto project building a “network of blockchains.” Organized by the nonprofit organization Interchain Foundation (ICF), Cosmos is most interested in helping different blockchains communicate with each other in a vast Web3 ecosystem. One way Cosmos hopes to spur innovation in crypto is by offering its SDK service to developers. Developers who use the Cosmos SDK can write open-source codes in the Go language and deploy a blockchain within the Cosmos network.  
3. Samsung Blockchain SDKs: Seoul-based electronics company Samsung now offers blockchain-specific SDKs for dApp developers. With the Samsung Platform SDK, you can access multiple tools, resources, and features dedicated to building dApps on Ethereum, Tron, and Ethereum-compatible blockchains like the BNB Smart Chain and Polygon.  
4. Tatum JS SDK: The Tatum JavaScript SDK is another popular toolkit that links with dozens of prominent blockchains. As the name suggests, coders can use JavaScript to create their dApps with this toolkit. A few blockchains the Tatum JS SDK interacts with include Ethereum, Bitcoin Cash, and Solana. 
5. Enjin SDK: Enjin is an Ethereum-based platform focused on blockchain-based gaming and NFTs. To help Web3 game developers create dApps and integrate NFTs into their designs, Enjin offers a suite of services like its SDK. Developers who download the Enjin SDK can use languages like Java, C#, and C++ to create P2E dApps. 

Wrapping up 

Unless you’re involved in software development, you won’t use an SDK directly. However, everyone nowadays uses a few apps that rely on SDKs. Without SDKs, we wouldn’t have access to many apps and services on the internet. 

SDKs may also play a significant role in Web3. Although crypto SDKs aren’t as prominent as those offered by big tech companies, they’re becoming more accessible to blockchain developers. The resources that blockchain SDKs offer can encourage more skilled coders to create dozens of dApps with unique use cases.

At Worldcoin, we aim to help increase awareness and usage of all things crypto. To help more people feel comfortable exploring Web3, we’re putting a share of our crypto in the hands of every individual on the planet for free. We’re also giving away DAI tokens to anyone who downloads our app. Subscribe to our YouTube channel to learn more about Worldcoin and the cryptocurrency market.