DOS, Windows, sharing, and mobile

Windows, when it arrived on the scene, changed the world of computing. Prior to Windows, DOS ruled the computing world, and it was a limited world. Windows expanded that world with new capabilities. In some ways, mobile operating systems (Android and iOS) move us back towards the ways of DOS.

IBM PCs (or compatibles, or near-compatibles) running DOS were simple devices. They could run one program at a time; running multiple programs at once was not possible. (Technically, it was possible with a "terminate and stay resident" function call, but such programs were few. For this essay, I'll stick to the "regular" programs.)

Windows brought us an expanded view of computing. Instead of running a single program at a time, Windows allowed for multiple. Windows provided a common way to present text and graphics on the screen, to print to printers, and to share data. Windows was a large step upward from the world of DOS.

Mobile operating systems -- Android and iOS -- provide a different experience. Instead of multiple applications and multiple windows, these operating systems present one application (or "app") at a time. Multiple apps may run, but only one has the screen. Thus, you can listen to music, check e-mail, and get a text message all at the same time. Mobile apps keep the multitasking aspect, but reduce the interaction to one app at a time.

Reducing the number of interactive apps to one is a reduction in capabilities, although it is a simpler experience, and one that makes sense for a phone. (I think it also makes sense for a tablet.)

What I don't see in the mobile operating systems (and what I don't see in Windows, either) is improvements in the ability to share data across applications. DOS had files and pipes (concepts lifted from Unix). Windows added the clipboard, and then Dynamic Data Exchange (DDE) and later, drag-and-drop. The clipboard was popular and is still used today. DDE never got traction, and drag-and-drop is limited to files.

Sharing data across applications is difficult. Each application has its own ideas about data. Word processors hold characters, words, sentences, paragraphs, and documents. Spreadsheets hold numeric values, formulas, cells, rows, columns, and sheets. Databases hold rows and columns -- or "documents" (different from word processor documents) for NoSQL databases. The transfer of data from one application to another is not obvious, and therefore the programming of such transfers is not obvious.

But Windows has had the clipboard for thirty years, and DDE and drag-and-drop for almost as long. Have we had no ideas in that time?

Perhaps our current mobile operating systems are the DOSes of today, waiting for a new, bold operating system to provide new capabilities.