US smartphone owners are keeping their devices for an average of 33 months

"U.S. consumers are holding onto their smartphones for an average of 33 months as a lack of innovation gives them reason to upgrade less frequently, a survey by Strategy Analytics found. The firm said consumers are very interested in next-generation 5G mobile service, although high smartphone prices will be a significant barrier to entry.
The average Apple smartphone has been active for 18 months, longer than the 16.5-month average for Samsung devices. The two companies remain dominant with brand loyalty of more than 70%, while other device makers like LG and Motorola see repeat purchase intentions of less than 50%.
Just 7% of U.S. consumers said they would spend over $1,000 on a new phone, while "wow features" are important to only about one-third of those surveyed. One out of four people said 5G will be important for their next mobile device, per Strategy Analytics."

Source:  Mobile Marketer, 23rd August 2019