When Apple announced the first Personal Digital Assistant, called the Newton Messagepad, in 1992, Microsoft's answer was the WinPad, which was to have the same portrait orientation as the MessagePad and supported apps built in Visual Basic. Note the similarities in names, and a big part of MessagePad was the NewtonScript programming language. #

WinPad never made it to market, instead we got Windows CE and the first handheld PCs. The clamshell handheld PCs were at least different than the MessagePad in that they had physical keyboards and looked like mini-PCs. For all practical purposes, Windows CE was a slimmed down Windows 95. #

The popularity of the Palm PDAs lead to Microsoft's Palm PC/Palm-size PC response, with the Windows 95 UI and a drop-down start button at the top left of the screen. #

In the fall of 1999 Microsoft announced the Pocket PC, the next iteration of the Palm-size PC that while it had a better name, came with the "big" UI innovation of moving the Start button from the top left of the screen to the bottom left of the screen.#

Fortunately for Microsoft, their mobile efforts were rescued by one of their hardware OEMs, Compaq. The iPaq, was nearly as slim as the Palm V and had unique expansion capbilities provided via a family of sleeves. In my opinion the iPaq single-handily accounted for Microsoft's increase in market share. #

Microsoft response to the Palm Treo was the Pocket PC Phone Edition, their response to Nokia's Symbian was the keyboard-driven, non-touchscreen Windows Smartphone.#

During the early 2000s Microsoft's Pocket PC gained market share, and thanks in large part to Palm's failings actually became the top mobile operating system. #

And then in 2007 Apple announced the iPhone, which sent Microsoft into a complete tailspin taking them three years to respond with a touch-screen driven device of their own, Windows Phone 7. #

As long back as the late 90s, early 2000s there was debate among mobile enthusiasts about whether Microsoft needed to manufacturer and sell their own devices. Even back then, users were frustrated with the fact that software upgrades did not appear on all devices because hardware manufactures chose not to provide them. (Sound familiar Android fans?) Finally in 2013 Microsoft buys Nokia in an effort to take control of their own fate, which we now know was another decision made too late.#

One can only wonder what might have been had Microsoft not been so committed to the Windows 95 UI on their mobile products back in 1999 and instead was willing back then to develop something like the Modern UI on Windows Phone 7. #