"Why didn’t HP pursue smart phones and a tablet?" In a word, Arrogance! At the Palo Alto site there was a conference room in 4 lower with demos of all the different use models of the Information Appliance (aka what we now know as a smart phone). Rumor has it that Steve Jobs got a look at it and that vision became the iPhone and brought over $800B into Apple. When Carly set up the Embedded and Personal Systems division to pursue that vision she also hired a president who's claim to fame was in changing the color of pagers from black to purple which drew in a younger crowd. This was the level of what CF was looking for, not the significant effort that Apple was willing to do. HP spent a year or two in search of the next "Purple Pager" and then she nuked the entire group when she bought Compaq. It still pains me to hear her talk about how wonderful she feels she was as CEO.
HP Stock at Carly's appointment as CEO (July 1999): $25.91
HP Stock at Carly's departure (July 2005): $10.98
(adjusted for 2:1 split in 2000 and departure of HPE in 2015)
APPL Stock (July 1999): $1.90
APPL Stock (July 2005): $6.09
(adjusted for 2:1 split in July 2000 and Feb 2005 and 7:1 July 2014)
iPhone release 2007
And then there is HP's (HPE) disastrous stab at playing in the cloud business, but that's another story.