One having a silent chat

• You shouldn't be a driver and this simultaneously
• One who shouldn't be driving
• One who might type "OMG" or "CYA"
• Today's teen, often
• One on the phone, often

Wiktionary Word definitions in Wiktionary
n. 1 One who texts; one who sends text messages. 2 ''(Australia'') a marker#English, felt-tipped pen

Wikipedia Word definitions in Wikipedia
Texter is a surname. Notable people with the surname include: Gilda Texter (born 1946), American costume designer John Texter (born 1949), American engineer