Intercepting API calls of your iOS app

When you work with APIs, you rely on the vendors API documentation.
However, API documentation is often not up to date or might be missing the latest API changes.

In this blog, I will describe how to intercept API calls from an iOS app.

What you need to get started:

• Charles Proxy
• iOS app
• Wifi with internet access

Let’s get started:

1. Install and start Charles Proxy
2. Configure proxy settings in Charles Proxy

   

3. Configure the proxy on your iPhone (Settings -> Wi-Fi -> Wi-Fi name -> Set HTTP PROXY to Manual

   

4. Start recording in Charles Proxy

   

5. Start using your iOS app and see all HTTP & HTTPS calls being populated under Structure

   

   You can open up each result and take a look at most of the details including any responses.

   TIP: Depending on the number of apps on your iPhone, you might want to filter for a specific URL like in Charles Proxy’s recording settings. This will greatly reduce the number of intercepted calls.