In 1884 Eastman developed a paper based film, which provided a significant savings in weight over glass plates, and changed his companies name to The Eastman Dry plate and Film Co. The following year, he introduced a rollfilm holder designed by William Walker. The Walker rollfilm holder was a success. He improved his film by making the emulsion removable from the paper backing. It could be transferred to glass plates in processing.
George Eastman was always striving to make photography easier and more convenient. He designed a camera around his rollfilm, The Eastman Detective camera, but it didn't sell well. In 1888 he introduced the Kodak. It was designed for people who wanted pictures, not people who were interested in photography. Prior to this, taking pictures required a darkroom. He coined the phrase "You push the button, we do the rest".
The rest of the story follows much the same path. Smaller companies that developed useful innovations were adsorbed, by fair means or foul.. Frank Brownell, cabinet maker turned camera maker, was hired. He developed many new designs, including the Brownie, which could be mass produced inexpensively, bringing picture taking to the general public.
Kodak expanded to create a worldwide market, first from manufacturing cameras in Canada to avoid high tariffs on imports outside of the British Empire, later to the UK and New Zealand. In 1932 he bought the Nagel Camerawerk, and retained Dr. August Nagel to design a line of affordable quality 35mm cameras. The Retina line was born. Later manufacturing was done in Australia, France and Brazil.
Diagnosed with terminal cancer, in 1932 George Eastman wrote a short note: "To my friends: My work is done. Why wait?". Sitting at the piano, he shot himself through the heart.