Cell phones of the future will be smaller, more flexible, have better graphics, and allow interaction with images and objects on the screen. Tablets are also expected to replace desktop computers as technologies upgrade. Desktop computers will continue improving over time with innovations like no visible keyboards or cords. Rogers' innovation adoption curve and Moore's extension of it explain how new technologies are gradually adopted in a bell-shaped pattern, with early adopters, a gap, and later mainstream users. This relates to cell phone upgrades following this pattern of gradual adoption. The uses and gratification theory also helps explain why people seek out new technologies to satisfy psychological needs.