How to host my ASP.Net admin panel without buying a domain?

I'm very new to web development but I will try to explain my question as best as I can.

I am making a basic admin panel program in C#. The admin panel will pass the data to android SQLite database using XML files, so XML file will be generated whenever admin updates data, and then it'll send the data to mobile phone.

Developing is all done but I need to host the admin panel in order to give XML links to my mobile app developer so she can create XML parser class or something. (please bear with me, I'm very new to programming). Anyway, I have no idea how to host it!

I've done some Googling but they all saying I need to buy domain name. I need to host it without buying domain.

Hope that's clear. Thanks in advance.