A Twitter spokesperson credited a team of volunteers:
Several weeks ago, we added translation support for right-to-left languages in the Twitter Translation Center, specifically for mobile.twitter.com. Since then, our awesome community of translators has been working hard to translate the mobile website. They completed the work for Arabic and Farsi quickly, and today we made them available to mobile.twitter.com users. We will continue to ship additional languages as they are ready.
The main Twitter site has been available in those two languages, as well as Hebrew and Urdu, since March (which also marked the first time Twitter was available in right-to-left languages). At that time, Twitter also thanked a team of 13,000 volunteers around the world, including many living in regions where Twitter is officially blocked.
It’s interesting that Twitter has decided to release its mobile site in Farsi and Arabic considering the key role some observers say the micro-blogging platform played in both the 2009 Iranian presidential election protests and the Arab Spring demonstrations. Farsi is the official language of Iran, where the government has enacted increasingly stringent controls over its already heavily censored version of the Internet. In September, the Iranian government announced that it’s going to launch its own domestic Internet, which will be fully operational by March 2013.
Twitter was initially seen as a key organizing tool during the 2009 Iranian presidential election protests, but observers have debated its role in organizing those demonstrations, as well as the Arab Spring.