Todoist added key collaboration tools earlier this year, and now it's going one step further for paid users. Users opting for premium account status will get Dropbox and Google Drive support to include cloud-stored files and documents with task lists. There's support for native files too, as you can now record/play audio files and attach photos via the web or mobile apps. Alongside the aforementioned task and project-sharing tools, folks using free accounts can access the new features when they're invited to work on a paid user's assignment. The company says that real-time collaboration and this new file-sharing add-on are filling its productivity quiver to launch a dedicated enterprise version in the near future. If combining your storage repository with your to-do list sounds like something you'd like to add to your workflow, there's a 30 percent discount on the $29 annual asking price for the next two days.