The news: Downloads of the Mastodon app have surged since Elon Musk’s takeover of Twitter.

• Mastodon downloads on iOS and Google Play skyrocketed by 6,380% worldwide between the weeks of October 15–26 and October 27–November 7, per Sensor Tower. News that Musk had completed the acquisition broke on October 27.
• The growth seems to have struck a nerve with Musk, who on Monday posted a series of since-deleted derogatory posts about Mastodon before tweeting that Twitter usage was at an “all-time high.”

Mastodon 101: Mastodon is a free, decentralized open-source platform that aims to provide “a viable alternative to Twitter.” It shares some similarities with Twitter, but there are important differences:

• Twitter is a singular platform, while anyone can create a network, called a server, on Mastodon. Usage rules are the same for all on Twitter, while users set and enforce regulations on individual Mastodon servers.
• Twitter uses an algorithm to serve content to users based on their previous activity and interests, while Mastodon serves content chronologically.
• Mastodon does not host ads. The nonprofit organization maintains its two main servers, mastodon.social and mastodon.online, while other servers are primarily funded by their users.

Between the lines: Twitter downloads are keeping steady.

• Worldwide Twitter app downloads stood at 486,186 on October 27 and reached as high as 636,768 on November 3, but were 526,844 on November 7, according to Apptopia.
• As of November 8, Twitter was the seventh most-downloaded app on iOS and Google Play in the US, per data.ai.

And downloads are only part of the story: Mastodon has hit 1 million monthly users, per a November 6 post by founder and CEO Eugen Rochko. That’s still a far cry from the 368.1 million monthly users we expect Twitter will have worldwide in 2022.

Yes, but: Prior to the takeover, we were already forecasting Twitter’s monthly user base in the US to decline 0.5% to 57.5 million this year. And close to half (489,003) of Mastodon’s monthly users are new as of October 27, per Rochko.

• Many of Twitter’s most active users are in revolt over the growth in controversial content, as well as Musk’s plan to make verification, an important security feature, a paid perk available only to Twitter Blue subscribers.
• Twitter usage has long fluctuated with the news cycle, peaking around big events (including the takeover saga). Musk’s tweet about Twitter usage being at an “all-time-high” is based on monetizable daily active users (mDAUs), a metric used only by Twitter that is more a measure of engagement rather than reach. As the dust around the deal settles, it’s likely that usage will normalize.

Our take: Consumers are increasingly experimenting with alternative social networks, and the turmoil at Twitter is adding fuel to that trend. But brands leaving Twitter won’t find Mastodon a “viable alternative.”

• Mastodon is just one platform in a sea of social apps, from Discord to Substack to Gas to Geneva, gaining traction among certain subsets of consumers, and its unfamiliar user interface will be a significant roadblock to widespread adoption.
• Without an ad business, there are few options for marketers on Mastodon. Its open-source model also makes it susceptible to brand safety issues, which many advertisers suspending campaigns on Twitter are attempting to avoid.