(I'm not sure I have this 100% right, but here it goes):

First Graphing Calculator: Casio 7000G in 1985

First Foldable/Clamshell Calculator: HP 28S. There is one on the market today, Casio fx-9860 Slim.

First one with Natural Input: HP 48S

First one with a Stylus: Casio Classpad 300

First one with a Touchpad: TI nSpire Touchpad

First one with "documents": I want to say the HP 38G/39G; I think that was slightly before Casio came out with their e-activity.

First one with external backup: HP 48S

First one I ever owned: TI 81 back in 1991 - I was in high school. The first HP graphing calculator I owned was the HP 48G in 2000. The first Casio graphing calculator I owned was the fx-Algebra 2 (I think it was 2004).