Manus and Devin get compared because they share the same headline idea: hand the agent a goal and it does the whole job on its own, no step-by-step supervision. But they live in different worlds, and the comparison is less "which is better" than "which problem do you have." Manus is a general-purpose autonomous agent. Devin is an autonomous software engineer. Pick by the work, not the benchmark.
Manus is built for open-ended knowledge work. Give it a goal, research a market, build a competitive analysis, gather and organize data, draft a document, and it plans the steps, works across the web and your tools, and returns a finished artifact. It runs asynchronously, so you start a job and come back to a result. Its strength is breadth: it will take on almost any multi-step task you can describe. Its weakness is the flip side of that autonomy, a vague brief can send it down the wrong path, and output quality varies with how complex the task is, so you review before you act.
Devin is built for one domain and goes deep in it: writing software. It reads a repository, plans a ticket, writes the code, runs the tests, and iterates in its own development environment until things pass. On well-scoped engineering tickets, bug fixes, small features, refactors, it behaves like a junior engineer who never sleeps. It is not a generalist; you would not ask it to do market research, and you should not ask it to "build my whole app" either. Scope it like a ticket and it delivers; hand it ambiguity and it churns.
Pricing works similarly in spirit: both bill on consumption, Manus on credits tied to task size, Devin on compute units as it works, so a low entry price sits in front of costs that scale with how hard you push them. Neither is a flat subscription you stop thinking about.
The honest take: there is almost no overlap. Choose Manus when you need open-ended research, analysis, or content produced end to end and value getting back a finished draft. Choose Devin when you have software tickets to offload and want an agent that writes, tests, and fixes code unattended. The only real shared lesson is the same for both: define the deliverable precisely, and review what the agent produces before you ship it.