37signals’ Jason Fried and David Heinemeier Hansson know the value of simplicity. 15 million people have used their flagship product, Basecamp. The cloud tool is notable, particularly because it simplifies communication and collaboration for one of the most complex tasks organizations face: project management. Fried and Heinemeier Hansson note in their best-selling business book, ReWork, the value of embracing constraints and pursuing simplicity. In fact, limiting the app’s features helped drive its success.

DayMap adopts the same worldview. The Whestone Apps’ program, priced at just $14.99 (USD) for the Mac and only $0.99 (USD) for the iPhone, is a small miracle. The day-planning software essentially provides simple to-do list functionality. Create a project. Add a task. Include descriptions and tags where necessary.

That’s been done before. Where other task management, to-do list, and productivity apps go bad is that they begin adding dozens of other features and capabilities — or they don’t offer smooth synchronization with a smartphone. And when they do, a critical function usually ends up missing, like assigning and moving tasks within a calendar view. Forget trying to view tasks on a calendar using most other task management programs. Thanks to an insatiable appetite for more functions and additional capabilities, such functionality typically becomes lost within a myriad of other features.

No more. DayMap has done it, and it works.

Using DayMap’s simple interface, which places color-coded projects and tasks at the top of a window and calendar days on the bottom, Mac users can now simply drag-and-drop tasks to a specific day and view individual tasks alongside calendared appointments.

DayMap includes the option for viewing the Apple Calendar’s appointments within its app. Just select Show Apple Calendar Events from DayMap’s View menu.

This is a big deal. I’ve been using computers since 1975. Rarely do I become giddy over a new innovative feature within a software program, but that’s just the sensation I experienced when I realized I could now view tasks alongside appointments and move elements, as necessary, using simple drag-and-drop action. The visual representation of a day’s appointments and tasks is where the app offers its unique value.

Because DayMap’s app includes an iPhone counterpart, it’s easy to add simple reminders and tasks on-the-fly when working remotely outside the office, and this is a critical requirement for most modern business workers. While the iPhone app doesn’t offer the combined task/calendar view, I don’t need that on my smartphone with its five-inch screen. That’s what my laptop is for. So, I appreciate Whetstone’s developers keeping the iPhone app lean and mean, focused merely on enabling viewing, adding, and completing tasks. Thanks to the iCloud, the iPhone app keeps my DayMap information seamlessly synchronized. The iPhone app is very easy to use, and its simplified focus is refreshing.

One of the most convenient features of DayMap is the ability to organizing tasks. Until a new task is associated with a project, new tasks conveniently sit within the app’s Inbox. They can then be dragged to any project using the Mac or iPhone apps.

Leveraging just a few keyboard shortcuts, it’s easy to quickly begin creating projects and tasks, marking items as complete, and moving day planner items to specific days. This is the task management app I’ve been seeking since I replaced my paper-based DayRunner in 2000.

What’s your favorite Mac or iOS app for staying organized? Share your opinion in the discussion thread below.