Charles: usage for native mobile application testing (IOS)

Mobile testing is new for me. I found extremely useful HTTP proxy tool Charles for monitoring traffic, which our mobile app sends/receives. It helped me to investigate bugs more deeply, not just their UI implication.

Set up Charles to see phone’s traffic

1. Install Charles on your computer.
2. Start Charles.
3. Make sure your phone and computer are connected to same WiFi network.
4. Find your network IP address in System Preferences -> Network.
5. Open WiFi settings on your phone: Settings -> WiFi -> {your WiFi network name} -> HTTP Proxy. Set proxy to Manual and enter your network IP address and Port (by default it’s 8888). Leave Authentication switched off.
   

   
6. Install root certificate on your IOS device, open following link in your phone browser: http://www.charlesproxy.com/getssl
7. In Charles add a domain which you want to monitor in Proxy -> SSL Proxying Settings; enable SSl Proxying:

9. Do any interactions in your app to make any HTTP calls, you should see a popup from Charles to confirm device usage.

Now you should see all calls, which your application makes and what are server responses.

Simulate Internet connection

First of all set up Charles on your computer (see steps above). To change your network connection settings do following steps:

1. In Charles open Proxy -> Throttle Settings. Enable throttling by checking check box:

2. Now you can select different throttle presets. You can set your custom network parameters or use ready settings like ‘3G’ throttle preset.

Useful article for setting up Charles with Android devices: http://jaanus.com/blog/2012/02/12/debugging-http-on-an-android-phone-or-tablet-with-charles-proxy-for-fun-and-profit/).

Enjoy your testing :)