In early 2013 I wrote the blog post Ambient Computing Challenge: Please Abstract My Digital Life. In it I lamented about the inessential complexity we all encounter living with a multitude of weakly integrated digital devices and services:
I simply want to think about all my “digital stuff” as things that are always there and always available. No matter where I am or which device I’m using.
… My attention should always be on “my stuff.” Different devices and different services should fade into the background.
In the eight years since I wrote that blog post not much has changed in how we think about and use our various devices. Each device is still a world unto itself. Sure, there are cloud applications and services that provide support for coordinating some of “my stuff” among devices. Collaborative applications and sync services are more common and more powerful—particularly if you restrict yourself to using devices from a single company’s ecosystem. But my various devices and their idiosyncratic differences have not “faded into the background.”
Why haven’t we done better? A big reason is conceptual inertia. It’s relatively easy for software developers to imagine and implement incremental improvement to the status quo. But before developers can create a new innovative system (or users can ask for one) they have to be able to envision it and have a vocabulary for talking about it. So, I’m going to coin a term, Personal Digital Habitat, for an alternative conceptual model for how we could integrate our personal digital devices. For now, I’ll abbreviate it as PDH because each for the individual words are important. However, if it catches on I suspect we will just say habitat, digihab, or just hab.
A Personal Digital Habitat is a federated multi-device information environment within which a person routinely dwells. It is associated with a personal identity and encompasses all the digital artifacts (information, data, applications, etc.) that the person owns or routinely accesses. A PDH overlays all of a person’s devices1The person’s general purpose computer-like devices, not the hundreds of special purpose devices such as “smart” light switches or appliances in the surrounding ambient computing environment. A PDH may mediate a person’s interaction with such ambient devices but such devices are not a federated part of the PDH. Should a smart watch be federated into a PDH? Yes, usually. How about a heart pacemaker? NO! and they will generally think about their digital artifacts in terms of common abstractions supported by the PDH rather than device- or silo-specific abstractions. But presentation and interaction techniques may vary to accommodate the physical characteristics of individual devices.
People will think of their PDH as the storage location of their data and other digital artifacts. They should not have to think about where among their devices the artifacts are physically stored. A PDH is responsible for making sure that artifacts are available from each of its federated devices when needed. As a digital repository, a PDH should be a “local-first software” system, meaning that it conforms to:
… a set of principles for software that enables both collaboration and ownership for users. Local-first ideals include the ability to work offline and collaborate across multiple devices, while also improving the security, privacy, long-term preservation, and user control of data.Martin Kleppmann, Adam Wiggins, Peter van Hardenberg, and Mark McGranaghan. Local-first software: you own your data, in spite of the cloud. 2019 ACM SIGPLAN International Symposium on New Ideas, New Paradigms, and Reflections on Programming and Software (Onward!), October 2019, pages 154–178. doi:10.1145/3359591.3359737
There is one important difference between my concept of a PDH and what Kieppmann, et al describe. They talk about the need to “synchronize” a user’s data that may be stored on multiple devices and this will certainly be a fundamental (and hopefully transparent) service provided by a PDH. But they also talk at length about multi-user collaboration where simultaneous editing may occur. With every person having their own PDH, support for inter-PDH collaborative editing will certainly be important. But I think focusing on multi-user collaboration is a distraction from the personal nature of a PDH. The design of a PDH should optimize for intra-PDH activities. At any point in time, a person’s attention is generally focused on one thing. We will rarely make simultaneous edits to a single digital artifact from multiple devices federated into our PDHs. But we will rapidly shift our attention (and our editing behaviors) among our devices. Tracking intra-PDH attention shifts is likely to be useful for intra-PDH data synchronization. I’m intrigued with understanding how we might use explicit attention shifts such as touching a keyboard or picking up a tablet as clues about user intent.
So let’s make this all a little more concrete by stepping through a usage scenario. Assume that I’m sitting at my desk, in front of a large display2Possibly hardwired to a “desktop” computer.. Also sitting on the desk is a laptop, a tablet with a stylus, and a “phone” is in my pocket. These devices are all federated parts of my PDH. Among other things, this means that I have access to the same artifacts from all the devices and that I can frictionlessly switch among them.
- Initially, I’m typing formatted text into an essay that is visible on the desktop display.
- I pick up the tablet. The draft essay with the text I just typed is visible.
- I use the stylus to drag apart two paragraphs creating a drawing area and then make a quick block diagram. As I draw on the tablet, the desktop display also updates with the diagram.
- As I look at my drawing in context, I notice a repeated word in the preceding paragraph so I use a scratch-out gesture to delete the extra word. That word disappears from the desktop display.
- I put down the tablet, shift my attention back to the large display, and use a mouse and keyboard to select items in the diagram and type labels for them. If I glance at the tablet, I will see the labels.
- Shifting back to tablet, I use the stylus to add a couple of missing lines to the diagram.
- Suddenly, the desk top speaker announces, “Time to walk to the bus stop, meeting with Erik at Starbucks in 30 minutes.” The announcement might have come from any of the devices, the PDH software is aware of the proximity of my devices and makes sure only one speaks the alert.
- I put the laptop into my bag, check that I have my phone, and head to the bus stop.
- I walk fast and when I get to the bus stop I see on my phone that the bus won’t arrive for 5 minutes.
- From the PDH recent activities list on the phone I open the draft essay and reread what I recently wrote and attach a voice note to one of the paragraphs.
- Latter, after the meeting, I stay at Starbucks for a while and use the laptop to continue working on my essay following the suggestions in the voice notes I made at the bus stop.
- …and life goes on in my Personal Digital Habitat…
Personal Digital Habitat is an aspirational metaphor. Such metaphors have had an important role in the evolution of our computing systems. In the 1980s and 90s it was the metaphor of a virtual desktop with direct manipulation of icons corresponding to metaphorical digital artifacts that made personal computers usable by a majority of humanity. Since then we added additional metaphors such as clouds, webs, and stores that sell apps. But our systems still primarily work in terms of one person using one physical “computer” at a time—even though many of us, in a given day, frequently switch our attention among multiple computers. Personal Digital Habitat is a metaphor that can help us imagine how to unify all our computer-based personal devices and simplify our digital lives.
This essay was inspired by a twitter thread from March 22, 2021. The thread includes discussion of some technical aspects PDHs. Future blog posts may talk about the technology and how we might go about creating them.
- 1The person’s general purpose computer-like devices, not the hundreds of special purpose devices such as “smart” light switches or appliances in the surrounding ambient computing environment. A PDH may mediate a person’s interaction with such ambient devices but such devices are not a federated part of the PDH. Should a smart watch be federated into a PDH? Yes, usually. How about a heart pacemaker? NO!
- 2Possibly hardwired to a “desktop” computer.