Wunderlist, the task management app with 9 million+ users, is adding a new feature to its web and mobile service: from today you will be able to link and access Dropbox documents through the app.

Dropbox will be live first on Wunderlist’s web app and Android app, with the feature coming up in the iOS coming any day now.

This is Wunderlist’s first full integration with a third-party app, and it’s important for a couple of reasons.

First, it positions Wunderlist as a much more useful app, a place not just where you list the things you have to do, but one where that you can actually work on them as well.

Second, it is the first of more integrations to come: “This is the kick off for more to come,” Benedikt Lehnert, the chief designer at 6Wunderkinder (the startup that makes Wunderlist). “With Dropbox, we have the most requested integration done.” Next up, from what I understand, will be integrations with other organising apps like Evernote, calendars from others like Google (right now you can export to Google’s calendar but you cannot import), and other third party apps that rely on you planning and scheduling things.

This also feels like something that was written in the stars… or at least the term sheets. Last year, when we discovered (and then confirmed) that 6Wunderkinder had raised $19 million led by Sequoia, the VC’s chairman Michael Moritz, who led the round, described Wunderlist as a natural complement to the functionality of two of its other portfolio companies, Evernote and Dropbox.

“Cloud-based applications is an area that Sequoia has liked for several years, and we see 6Wunderkinder as a continuation of the investment interest that first led us to Dropbox and then to Evernote and now to 6Wunderkinder,” he said in an interview.

Thus, it seemed like only a matter of time before we started to see more linkage between the three — but not more than that, at least for now. Lehnert only gave me a nervous laugh and a short “no” when I asked him if Wunderlist had been approached by anyone like, say, Dropbox as a possible acquisition.

As it happens, 6Wunderkinder and Dropbox had already been speaking, even before Sequoia came on board as an investor. “We share the same philosophies — it’s not just that the products make sense,” Lehnert says.

The groundwork for expanding the product was also laid earlier this summer when Wunderlist 3 was released, which rearchitected the whole product to make it much more elastic and able to accommodate other services within it — the move from becoming a service to a platform. You add and access Dropbox files through the details menu of an individual task item, which positions the menu as the place where other integrations will also likely appear down the road.

Wunderlist is one of the bigger task managing apps out in the market today in terms of active users, but it’s not the only one, and not the only one working on being more than the sum of its parts. Sunrise, for example, already integrates with other third-party services. Lehnert says it doesn’t see Sunrise as a competitor, however.

“Sunrise is a calendar and we are not. We are about getting stuff done and organised. It’s just a different scope. We’re not even looking at Sunrise as a competitor,” he says.

One of the unique angles that Wunderkinder is pursuing is the idea of creating a “to-do” set where you can successfully merge work and personal tasks in a very simple way.

This is partly spurred by the fact that Wunderlist has been building out a premium business for working people, and in that sense almost competes as much against apps like Flow as it does Sunrise. It currently has some 50,000 businesses using the product but will not spell out what that means in terms of user numbers.

It’s about tackling that group and giving them a more “consumerized” enterprise product, he says. “People don’t want to switch tools all the time,” he says. “It’s about broadening the scope of the product to serve both in the perfect way, and it’s what we see happening already.” He says Wunderlist is already, for example, used for grocery lists for couples but also to organise marketing projects. “We will put more into team functionalities and collaboration, giving you pop-up reminders just when you need them.”

Today the app still counts the U.S. as its biggest market — 30% of its users hail from there — while China is now in the number-two position, with Europe collectively in third.