Microsoft says it designed Windows 8, reviewed, to work across all devices, from the tiny screen of a smartphone right up to the biggest PC monitor. The tiled interface does this job pretty well, but as I've said before, Windows 8 on the desktop feels very much like two OSes in one.

I've been using Windows 8 as my main OS for a good five months now, and almost never use the new Start screen. It's partly because there's no need to, apart from launching the odd app for which I don't have a desktop shortcut, and partly due to the fact that there are still no killer apps in the Windows Store to persuade me to ditch the desktop equivalent.

A bigger issue, though, is that the two halves of Windows 8 on the desktop aren't integrated in any meaningful way. It's obvious that this is a deliberate decision on Microsoft's part as live tiles could easily have been introduced to the traditional desktop to merge the old and new.

Already, hacks are appearing to bring back the old Windows 7 Start menu, but Windows 8 could have had an updated Start menu with live tiles and 'Charms'. Alternatively, live tiles could have been made a part of the desktop itself (anyone remember Active Desktop?), or displayed on a sidebar as the old Gadgets were.

It all points to a future where, perhaps even in Windows 9, the desktop will be relegated to history and users will be forced to rely on new-style apps. That approach may be a mistake, as apps (just like the modern UI itself) are designed for touch operation, which means big buttons, icons and text.

It seems pretty unlikely that millions of PC users will upgrade their monitors to touchscreens any time soon, or that anyone will really use their new touchscreen laptop or all-in-one PC once the novelty wears off - and arm ache sets in.

What this means is that the humble keyboard and mouse will remain the way that people interact with their PC. App designers would do well to bear this in mind, as well as to make sure their apps don't only deliver a 'dumbed-down' feature set. PCs are more powerful than a tablet or smartphone and I for one don't simply want a bunch of tablet-style apps which don't offer the power or control that existing programs do.

Windows 8 may or may not be a great success on tablets, smartphones and other touchscreen devices, but here's hoping that Windows 9 doesn't drive loyal Windows users to Mac OS instead.

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