I'm using a little modified implementaition of this: http://www.arduinesp.com/thingspeak on my esp.
The problem is everything works fine when im using normal internet connection, but when i connect with a 3G-wifi router the data from esp is not reaching ThingSpeak server.
When i connect a laptop to this router I can browse webpages with no problem so i figure there should be no problem with sending POST request outside. I know some mobile internet providers block incoming connection ports, but i'm not trying to connect to my esp from the outside network, I just want to send a simple POST request to the srever.
Any ideas? I'm quite new to the esp so maybe I'm missing something obvious.