Meta's Muse Hit 10 Million US Downloads in 40 Days. Only 11 Apps Have Ever Done That.

Key points

• Muse, Meta's AI agent app, reached 10.9 million total downloads by day 40, with 10.2 million of those in the United States, according to Sensor Tower data.
• Only 11 other apps in history have hit 10 million US downloads within 40 days of launch, most of them mobile games.
• Muse's 7-day US retention rate of 30% is nearly double the 19% average seen by ChatGPT, Claude and Grok combined.
• Meta directed 39% of its total advertising spend toward Muse in October 2026, up from 23% in September.
• Muse's US daily active users reached 2.5 million for the first time on October 16, a 15% week-over-week rise.

Very few apps top the charts and stay there. Muse is looking like one of them.

Market intelligence firm Sensor Tower, first reported by TechCrunch AI, put hard numbers to what many had suspected: Meta's AI agent app, software that can carry out tasks on your behalf like booking a table or finding a product, has cleared 10 million US downloads in its first 40 days. That milestone puts it in a list of twelve apps total, the last of which was Meta's own Threads in July 2023. Before Threads, every other app on that list was either a mobile game (Fortnite, Pokémon GO, PUBG Mobile) or Disney+.

The downloads figure is striking. The more telling number is what happens after people install it.

Are people actually using Muse, or just downloading it?

They're using it. Muse's 7-day US retention rate sits at 30% and its 14-day rate at 23%, against a competitor average of 19% and 16% respectively. Retention rate is the share of people who installed an app and are still opening it days later. A higher number means fewer people tried it once and forgot about it.

For comparison, ChatGPT, a large language model app from OpenAI, pulled in 3.7 million US downloads in its first 40 days. Grok, from xAI, saw 500,000. Claude, Anthropic's chatbot app, reached 200,000. Muse's 10.2 million makes those figures look modest, though ChatGPT did beat Muse globally, reaching roughly 15 million downloads worldwide in the same window. That gap has a straightforward explanation: Muse is currently available only in the US and Canada, while ChatGPT launched into Japan, Brazil and Germany simultaneously, among other markets.

Muse's daily active user count hit 2.5 million on October 16, the first time it has crossed that mark.

How much of this is just heavy advertising?

A significant share of the early push is bought, not organic. Meta allocated 39% of its entire advertising budget to Muse in October 2026, up from 23% in September. The app climbed from the 73rd largest US brand by advertising impressions in September to 21st in October. That kind of spend can manufacture downloads. What it cannot easily manufacture is a 30% 7-day retention rate.

Meta also has a structural advantage no standalone AI app can buy: a family of apps, Facebook and Instagram among them, with 3.6 billion daily active users as of October 2026. That audience is a free distribution channel, the same one that helped Threads reach scale before it. We covered how the Muse Charm wearable works as a physical interface for the agent on 27 September, and our earlier report from 23 September found that privacy advocates were already flagging Muse's data collection as the real product. Both point to a company treating Muse as a platform, not just an app.

Muse has held the number-one spot on the US App Store every day since launch except October 19, when streaming app Kick briefly edged it out. It has also ranked first on Google Play for the past 30 days.

What to watch: Retention curves tend to fall sharply between weeks two and eight. Muse's 14-day rate of 23% is healthy, but the figure Sensor Tower has not yet published for the weeks beyond that will say far more about whether this is a lasting habit or a very well-marketed launch.