Microsoft has released one of its most detailed looks yet at how people use Copilot — and the results suggest the AI assistant plays different roles depending on time of day and the device.
In a new preprint titled “It’s About Time: The Copilot Usage Report 2025,” Microsoft AI researchers analyzed 37.5 million de-identified Copilot conversations between January and September of this year. Enterprise and school accounts were excluded, and machine classifiers labeled each chat by topic and “intent,” such as searching for information, getting advice, or creating content.
The top-line finding: on desktop computers, Copilot usage centers on work and technical questions during business hours. On mobile, it’s about health — all day, every day.
“Health and Fitness” paired with information-seeking was the single most common topic-intent combination for mobile users, and stayed in the top spot every hour of the day across the nine-month window. The paper suggests this shows how people increasingly treat Copilot on their phones as a private advisor for personal questions, not just a search tool.
On PCs, “Work and Career” overtakes “Technology” as the top topic between 8 a.m. and 5 p.m., mirroring a traditional office schedule. Other work-related topics such as science and education also rise during the day and fade overnight.
“The contrast between the desktop’s professional utility and the mobile device’s intimate consultation suggests that users are engaging with a single system in two ways: a colleague at their desk and a confidant in their pocket,” Microsoft wrote in the study.
Compared with January, the September data from Microsoft’s study shows fewer programming conversations and more activity around culture and history — a sign, the researchers say, that usage has broadened beyond early technical adopters into more mainstream, non-developer use cases.
Usage reports from OpenAI and Anthropic found similar consumer patterns, with many people using ChatGPT and Claude for practical guidance, information, and writing help in their personal lives. Microsoft’s new Copilot study adds a sharper twist: on desktops, AI looks like a co-worker; on phones, it looks a lot more like a health and life adviser.
In a companion blog post, Microsoft said the study shows how Copilot “is way more than a tool: it’s a vital companion for life’s big and small moments.”
The study highlights a rise in advice-seeking, particularly around personal topics. This suggests people are turning to AI not just to offload tasks but to help make decisions — which could raise the stakes for model builders around accuracy, trust and accountability.
Microsoft’s research team included Microsoft AI CEO Mustafa Suleyman as a co-author. Each conversation was automatically stripped of personally identifiable information and no human reviewers saw the underlying chats, according to the paper.
