Vodafone recently released a "Law Enforcement Disclosure Report”. Because Vodafone provides services in so many countries, this provides a unique insight into the range of surveillance capabilities and requirements across a spectrum of nations. In six countries they are required to provide direct connections to their network for the local government. This allows those governments to capture content and meta-data without making individual requests to Vodafone. They are not saying which 6 countries those are out of fear of penalties or retaliation.
In Albania, Egypt, Hungary, India, Malta, Qatar, Romania, South Africa and Turkey it is illegal to reveal information about various kinds of intercepts, so the report does not provide information on those countries.
The report also provides good information on the frequency of requests for information from various countries.
One lesson from this is, despite the impression one might have gotten from the Snowden leaks, the US is far from the only country doing this kind of surveillance.