Apple Inc. /zigman2/quotes/202934861/composite AAPL +0.17% could get a boost from expanded uptake of iPhone trade-in programs, Morgan Stanley's Katy Huberty wrote Monday. She upped her price target on Apple's stock to $419 from $340, while maintaining an overweight rating and arguing that improved adoption of iPhone trade-ins creates a "sustainable competitive advantage" for Apple. She said that adoption of device trade-in programs in general is on the rise, with 48% of people already taking advantage, according to a recent Morgan Stanley survey, while 77% of consumers surveyed said that they anticipate that they'll trade in an electronic device by 2021. She calculates that if iPhone trade-in adoption were to reach 77%, iPhone affordability will improve by at least 10% in the next five years. In her view, a growing interest in sustainability could help drive a further shift in consumer behavior. Apple shares are up 3.6% in Monday trading. The stock has rallied 45% over the past three months as the Dow Jones Industrial Average /zigman2/quotes/210598065/realtime DJIA -0.07% has gained 13%.