Here is a spreadsheet with a list of world countries and which ones have access to Apple App Store and Google Play. I’ve needed this a few times and haven’t found a consolidated chart before.
For Google Play I’ve marked up the countries which allow the price to be overridden in the local county and where you can limit distribution by mobile carrier.
I’m interested to know how people in the countries without stores get access to apps. My guess is that the people in those countries who can afford a smartphone either have access to foreign credit cards or never pay for apps/content and just use free apps.