How did technology in the 1920s influence the American lifestyle?
Technology affected American lifestyles in two main ways.
First, it gave Americans more leisure time. By the 1920s, there were many more labor saving devices, particularly ones that reduced the difficulty of housework. These gave Americans more time to do things other than simply working.
Second, technology gave Americans more things to do with that newly-found spare time. The invention of radio and the boom in movies, combined with the growing availability of cars, allowed Americans to pursue a lifestyle that was much more centered around fun than it ever had been before.
Another thread here on Enotes, the one about Guns, Germs and Steel, suggests that metallurgy has something to do with changes in culture. With that in mind, technological advances which made possible the efficient production of steel and aluminum must have made possible the railroads, the cars, and the aircraft which were available in the 1920's.
An alloy called Vanadium steel is said to have made possible the production of cars which could take the punishment of country roads.
The Wright Brothers' flyer used an aluminum engine.
Transcontinental Air Transport began operations in July 1929, as the first company to coordinate air and rail service across the United States.
The Pennsylvania Railroad carried passengers by train from New York to Columbus, Ohio. Ford Trimotor aircraft flew passengers to Waynoka, OK where they boarded a Santa Fe Train for Clovis NM. Another Ford Trimoter aircraft completed the trip to Los Angeles.
The coast to coast trip lasted forty-eight hours.
As near as I can tell, this story (see link) is set in the early 1930's, but my great grandmother, age 90, says that in the 1920's people went to the movies in the evening. Prime time for radio was after the movies finished, and people gathered in houses with radios "to watch" the radio like people in the story. Also, as the story suggests, people traveled by train.
Like the story in posting #2 suggests, commercial radio became popular during the 1920's.
The triode, a vacuum tube that works something like a transistor, made that possible.