When it comes to integrating a third party’s services with your own, APIs are often the way to go. And with good reason, APIs provide an interface for different pieces of software to talk to one another and they specify how software should interact. In short, they help developers to leverage existing software for use in their applications instead of having to reinvent the wheel every time. Then of course there are software development kits (SDKs) that allow developers to interact directly with APIs in their code of choice.
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Why to Build an App With an SDK Instead of an API