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Setting up Fiddler to debug analytics requests from iOS devices

September 19, 2017 Comments Off on Setting up Fiddler to debug analytics requests from iOS devices By Michael Lee

Here are the steps to get Fiddler setup to capture traffics from iOS device, not all the steps are necessary, depending on how much tweaks you’ve made to your PC.

Step 1 – Install Fiddler…obviously

Step 2 – Make sure you are not on any kind of VPN

Step 3 – Window Setting (Let’s just make sure nothing stops us from what we are trying to do)

Temporary Turn off firewall – I”ve found cases that window firewall prevents this from working.

 

Make your PC discoverable. (For my version of Window 10, for whatever reasons, having this OFF prevents Charles from connecting to my PC, let’s just make sure that this is set to ON)

 

Step 4 – Fiddler Settings – Make sure your Fiddler has the settings below.

Let Fiddler acts as a system proxy.

If the app your debugging uses HTTPS, check the box below.

Uncheck filter, and let everything pass through for now. We want to get it working first.

 

Step 5 – Connect your iPhone to your computer.  The goal of this step is to use your PC as the server for your iPhone to get online, so all traffic go through your PC first.

In Fiddler, at UPPER RIGHT CORNER, there is a little icon that shows your current IP address.

 

 

 

 

 

 

Double check your computer and the iPhone is connected to the same network. In your iPhone, go to Setting->Wifi->Edit the current Wifi network, enter the IP address of your PC(shown above) as the server, and 8888 as the port. Then click Renew Lease.

Step 5 – Verify that your iPhone is connected to your PC, and the Internet.

Restart Fiddler, it helps sometimes.  On your iPhone, go to yahoo.com using Safari, if everything is working correctly, you’ll see all the request from your browser in Fiddler.  If you are not debugging HTTPS traffic, this is all you need.

 

If your are not able to get online from your iPhone, that means either something from Window is blocking Fiddler connection or something within the Fiddler setting that’s not acting as a proxy.

 

Step 6 – Installing SSL Certificate for seeing HTTPS requests.

Make sure your phone is still connected to your computer, and go to this URL from Safari

http://ipv4.fiddler:8888/

You should see this page, and click on this link to download the Fiddler Root Certificate.

Make sure you click Allow

If the Fiddler Certificate is installed correctly, you’ll see something like this, as  you can see, I’ve setup my Charles as well.

Alright, if you got to this far, all of the hard stuffs are done, but….there is One More Thing…….Go to Setting->General->About->Certificate Trust Setting, and make sure the iPhone trusts the Fiddler Certificate you just installed.

Step 7 – Verify that you are able to see encrypted HTTPS information.

If everything is working correctly, you’ll able to see HTTPS requests from your app.

Step 8 – Now turn your filter back on, to see only the stuff  you want to see, whether it’s ‘omtrdc.net’ for Adobe Analytics or ‘google-analytics.com’ for Google Analytics. You are all done….

 

If you prefer the official documentation from Fiddler, it’s here, it has all the details, and steps, and features of Fiddler.

http://docs.telerik.com/fiddler/Configure-Fiddler/Tasks/ConfigureForiOS

 

Happy debugging….