Saudi and Indonesia are two countries known for the fact that most internet users don't have a PC, but access the internet through mobile.
"Our graph with Twitter penetration numbers clearly shows a number of green fields for Twitter. In big countries like Nigeria, Germany and India Twitter usage is still low," the study said.
China is not listed because Twitter is banned from China and therefore the Chinese microblogging platform Weibo has no competition.
"Twitter users are young, on average 24 years. The average male is 26 years old, the average female 22 years old. Teenagers dominate Twitter. Only 20 per cent of the tweeps are older than 30," according to the study.
The top ten countries with highest active monthly users of Twitter are: 1 Saudi Arabia, 2 Indonesia, 3 Spain, 4 Venezuela, 5 Argentina, 6 UK, 7 Netherlands, 8 US, 9 Japan and 10 Colombia.
