Before the smartphone or tablet, there was the PDA (personal digital assistant), and PalmPilot was the king. All-in-one smartphones led by RIM's BlackBerry killed the PDA in the early 2000's. However, Palm adapted and over the years released fine smartphones like the Palm Treo, the Centro, and the Pre. It also developed a mobile OS, called WebOS, in 2009 and released it on the Palm Pre. But the Pre's sales were lackluster and it turned out to be Palm's last product. The company was bought by HP in 2010 and the Palm brand and WebOS have both been discontinued.
[ A Palm Technology Timeline ]
[ From Palm Pilot to Palm Pre: A Brief History of Palm's Handhelds ]