Handy
wiktionary
From Middle English handy, hondi (attested in personal names), alteration of earlier hendi(“handy, skillful”), from Old English hendiġ(“skillful”) (as in listhendiġ(“skilled in art”)), from Proto-Germanic *handugaz(“handy, skillful, nimble”), from *handuz(“hand”), equivalent to hand + -y. Cognate with Middle Low German handich(“skillful, apt”), Middle High German handec, hendec(“manual, hand-held”), Old Norse hǫndugr(“efficient”), Gothic 𐌷𐌰𐌽𐌳𐌿𐌲𐍃( handugs, “wise, clever”). Akin to Dutch handig(“handy”), Norwegian hendig(“handy”), Swedish händig(“handy”).
hand + -y(“diminutive suffix”)
Clipping of handgun + -y(“diminutive suffix”)
Disputed; see German Handy: according to some commentators, this meaning is originally from German (a condensed form of Handfunktelefon), whereas others claim there was an early, but now neglected, antetype of it in English (from etymology 1).
etymonline
handy (adj.)
c. 1300, "skilled with the hands" (implied in surnames), from hand (n.) + -y (2). Meaning "conveniently accessible" is from 1640s.
