In the past few days, Mastodon is getting popular in Japan. Mastodon is introduced in Yahoo! News and then it caused a buzz among JapaneseTwitter Users.
The features of Mastodon is almost same as Twitter. But Twitter allows users to write a tweet until 140 characters but on the other hand, Mastodon allows maximum 500 characters tweet.
The biggest difference between Twitter and Mastodon is maintainability. In other words, if the firm Twitter bankrupt, the service Twitter might be stopped. But in case of Mastodon, it is provided as an open source software. It means, anyone can launch an instance of Mastodon. And also if one of Mastodon instanced is alive, the users can continue to use Mastodon. As of April 13th 2017, there are more than 500 instances all over the world. In japan, https://mstdn.jp is the most popular instance created by @nullkal considered 22 years old student.
Some Japanese users are confusing about how to use Mastodon but pleased that there is no advertisement in timeline unlike Twitter and it allows 500 characters tweet.
There is a rumor in Japan that Twitter is going to charge for their service. If so, it is considered that many users will transfer from Twitter to Mastodon.