Microbrowser

A mobile browser is a web browser designed for use on a mobile device such as a mobile phone or PDA. Mobile browsers are optimized so as to display Web content most effectively for small screens on portable devices. Mobile browser software must be small and efficient to accommodate the low memory capacity and low-bandwidth of wireless handheld devices. Typically they were stripped-down web browsers, but some more modern mobile browsers can handle more recent technologies like CSS 2.1, JavaScript, and Ajax.

Websites designed for access from these browsers are referred to as wireless portals or collectively as the Mobile Web. They may automatically create "mobile" versions of each page, for example this one.

The mobile browser usually connects via cellular network, or increasingly via Wireless LAN, using standard HTTP over TCP/IP and displays web pages written in HTML, XHTML Mobile Profile (WAP 2.0), or WML (which evolved from HDML). WML and HDML are stripped-down formats suitable for transmission across limited bandwidth, and wireless data connection called . In Japan, DoCoMo defined the i-mode service based on i-mode HTML, which is an extension of Compact HTML (C-HTML), a simple subset of HTML.

WAP 2.0 specifies XHTML Mobile Profile plus WAP CSS, subsets of the W3C's standard XHTML and CSS with minor mobile extensions.

Newer mobile browsers are full-featured Web browsers capable of HTML, CSS, ECMAScript, as well as mobile technologies such as WML, i-mode HTML, or cHTML.

...
Wikipedia