The last Presidential elections in the US (2016) were overshadowed by many controversies, one of the main ones being the Russians were able to influence many American voters on Facebook. Post the US elections, other countries too warned Facebook of meddling with their elections (Germany).
Twitter has been gaining substantial user base from India. Just a year back this article said Twitter was yet to gain popularity in India. In March 2009 the traffic from India went up by 74%, but as the comments in that posting indicates when you start from zero the growth curve always looks impressive. The profile of Twitters from India is pretty interesting.