I am facing a real world issue that prevents me from using Bitcoin.
I live in Pakistan and for last three days cellular internet service all across the country is suspended because of prevailing law and order situation. Internet is working on fixed line connection that is reaching homes. So there is still some connectivity available.
If government shut down internet service even on fixed line connection then there will be complete internet blackout in the country and in that situation we cant use bitcoin.
I think this is also one of limitation of bitcoin that we need internet to use it.
I've heard in some African countries they started offering an SMS service for Bitcoin transactions which allows users to send/receive Bitcoin without internet access (and even without a smartphone). Not sure how it works though and if they're going to start offering it in other developing countries.