Match the term and the definition.
browser---nanobot---e-reader—smartphone---
1.a device or application to facilitate or enhance the reading of electronic material
2.a computer program with a graphical user interface for displaying HTML files, used to navigate the World Wide Web
3.a cellular phone that incorporates a palmtop computer or PDА
4.a hypothetical, very small, self-propelled machine, esp. one that has some degree of autonomy and can reproduce