Have Microsoft Windows tablet computer sales been significant?

Question

When people talk about the iPad they often mention that Windows-based tablet computers never took off (never had significant sales). Is this true? Did any company ever make make money building/selling Windows-based tablet computers?

Answer 1

Windows Tablet Sales Finally Being Tracked, Not in Last Place (sourced from some company named "Strategy Analytics" with the full report costing $6K), data for Q2/2011:

Millions of units shipped, Q2/2011:

iOS:     9.3 Million
Android: 4.6 Million
Windows: 0.8 Million
QNX:     0.6 Million
Others:  0.1 Million

% Global Market Share, Q2/2011:

iOS:     61.3%
Android: 30.1%
Windows: 4.6%
QNX:     3.3%
Others:  0.3%

Answer 2

20 years of trying has only created niche markets for Windows Tablets

It is worth reviewing a little history before attempting an answer to this question. The question asks whether Windows tablet PCs have ever been successful. I think this refers to Microsoft's Windows XP tablet edition in 2001. But Microsoft had launched a tablet OS in 1991. And even that wasn't the first (see potted history here). The fact that much of this history is forgotten is a product of the lack of success of these products. Here is part of the story as told by informationweek in january 2010:

Between 1992 and 1994, a number of companies introduced hardware to run Windows for Pen Computing or PenPoint. Among them were EO, NCR, Samsung ... Dauphin, Fujitsu, TelePad, Compaq, Toshiba, and IBM. Few people remember that the original IBM ThinkPad was, as the name implies, a slate computer.

The computer press was first enthusiastic, then very critical when pen computers did not sell. They measured pen computers against desktop PCs with Windows software and most of them found pen tablets difficult to use. They also criticized handwriting recognition and said it did not work. After that, pen computer companies failed.

Momenta closed in 1992. They had used up US$40 million in venture capital. Samsung and NCR did not introduce new products. Pen pioneer GRiD was bought by AST for its manufacturing capacity. AST stopped all pen projects. Dauphin, which was started by a Korean businessman named Alan Yong, went bankrupt, owing IBM over $40 million. GO was taken over by AT&T, and AT&T closed the company in August 1994 (after the memorable "fax on the beach" TV commercials). GO had lost almost US$70 million in venture capital. Compaq, IBM, NEC, and Toshiba all stopped making consumer market pen products in 1994 and 1995.

So the first wave didn't make anyone any money.

The second wave could be argued to start in 2001 with this (from a 2005 article looking back on developments):

Gates showed prototype Tablet PCs at the Comdex show in Las Vegas in 2001 -- a year ahead of their 2002 launch -- and at the show said in a company news release, "It's a PC that is virtually without limits and within five years I predict it will be the most popular form of PC sold in America."

The article further comments:

It's now a little over three and a half years into the time period he set and to-date Tablet PC has managed to do only marginally better than the now defunct trade show. A handful of vendors market Tablet PCs, but specialist markets like health care account for a large percentage of sales. Other users and those in business have yet to take to the form-factor in a big way.

It also suggests that just over half a million tablets shipped in 2004. This number sounds optiistic compred to the one hard number I've found so far which unfortunately only covers European sales. Canalys estimate that they were only about 33,000 in 2004.

Unfortunately, few research reports or forecasts from the 2001-2009 period are easy to find (perhaps because nobody likes to see old but failed forecasts). But this quote from the New York Times in 2009 (so pre iPad) and commenting on the Bill gates forecast quoted above sums up what seems to be the accepted wisdom:

Tablets running Windows sell only a few hundred thousand units a year, mostly in business fields like health care and financial services.

This suggests that they have never accounted for more that a fraction of 1% of PC sales (which were >300m in 2010).