What Application is
Used interchangeably with program and software, this is a general term for a program that performs specific tasks, such as word processing, database management, e-mail sending or retrieval, or Web browsing. Unlike system software, which maintains and organizes the computer system (such as the operating system), an app is an end-user program.
The meaning of Browser
A program used to view, download, upload, surf, or otherwise access documents (for example, Web pages) on the Internet. Netscape Navigator and Internet Explorer are well-known "Web browsers" that enable you to view and interact with Web sites.
Browsers read pages that are "marked up" or coded (usually in HTML but not always). These pages reside on servers. The browsers interpret the code into what we see rendered as a Web page. As well-designed software programs, browsers contain a variety of tools, including bookmarks and the back button, that make "surfing the Net" more enjoyable. You will need a browser to "get on the Web." Visit this definition on NetLingo.com for a link to product reviews and free downloads.