When you say "Debugging my mobile app" can you be specific about what the client and server are in this case?
If you debug other sites (e.g. Google, etc) is it also slow, or is it only slow when you debug the mobile app?
The only thing I can think to try is to set the EgressIP
preference to the IP address of the mobile interface: http://fiddler.wikidot.com/egressip
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