Army previously held a senior finance position at HealthTech Holdings.
Kavthekar was CFO of health and wellness solutions at Sears Holdings.
Smith also works as executive vice president. His retirement is effective at the end of August.
Wittman was senior vice president and CFO at Motorola Mobility after it was purchased by Google. She will replace Dropbox CFO Sujay Jaswa, who will continue as a special adviser.
Bready, a 20-year industry veteran, most recently served as CFO at ITC Holdings.
Bertolini was executive vice president and CFO at Schering-Plough until 2009, when the company merged with Merck & Co.