My mobile data provider seems to block incoming packets... (but I can receive if initiated from my phone (as in ftp), so maybe it's just that my IP address isn't known?) I couldn't work it out.
If you are on IPV6 you most probably will have public unique IP and should be able to access a website hosted on phone without any issue. ISP might not be explicitly blocking incoming packets. NAT was a necessary evil that we needed when we had limited address space. We should move to Ipv6 as early as possible and kill NAT. I think that will open up tonne of opportunities.