Lilina is an open source PHP application for aggregating feeds from a web-based interface.

It supports RSS, Atom & podcasts inside them. It is also possible to import/export feeds with an OPML file.

The application only requires PHP(5) to run & makes use of 2 built-in libraries: HTML Purifier and SimplePie.

Lilina has a plugin system for extending its capabilities & the look/feel can be customized with the theming support.

Gregarius is an open source web based feed reader. It is similar to Google Reader but you can install in on your servers.

It has a very simple & functional interface with a password protected administration area.

This feed reader has Ajaxed item tagging & full-text search features. It is committed to web standards: renders XHTML/CSS, supports OPML.

The application is built with PHP & uses MySQL or SQLite for storing the data.

With a getting active community, Gregarius has multiple themes & plugins.

PHP RSS Parsers are what many PHP developers looking for these days as every web application or website has some RSS input or output.

RSS parsers make the use of RSS simpler as they have overcame the known RSS parsing difficulties.

WebResourcesDepot have collected the most popular free RSS Parsers coded with PHP:

SimplePie

SimplePie is a PHP code library that makes it very easy to use RSS & Atom feeds. SimplePie is fast and standards compliant as it supports:

• RSS 0.90
• RSS 0.91 (Netscape)
• RSS 0.91 (Userland)
• RSS 0.92
• RSS 1.0
• RSS 2.0
• Atom 0.3
• Atom 1.0

This PHP RSS parser class has also plugins for favorite web services.

lastRSS

lastRSS is also a simple yet powerful PHP class for parsing RSS feeds.

• All RSS versions supported (0.9, 1.0 and 2.0)
• Transparent cache (doesn’t cache RSS file directly, neither HTML output, but serialized variable; cached data isn’t parsed every time, but you can still access individual fields)
• pubDate/lastBuildDate conversion to any date/time format
• Character encoding conversion (all encodings supported by iconv library)
• Returns an associative array with RSS fields
• Regullar expression parsing (very quick)
• Strips HTML from description (both hard-coded and entity-coded)
• Optional limit the number of returned items
• Two ways how to proceed CDATA information (get/strip CDATA content)

MagpieRSS

This PHP RSS parser class also supports well known feed formats like RSS 1.0, RSS 2.0 & Atom.

• Easy to use
• Parses most RSS formats
• Integrated Object Cache
• HTTP Conditional GETs
• Configurable
• Modular

Zend_Feed

Zend_Feed provides functionality for consuming RSS and Atom feeds. It provides a natural syntax for accessing elements of feeds, feed attributes, and entry attributes. Zend_Feed also has extensive support for modifying feed and entry structure with the same natural syntax, and turning the result back into XML. In the future, this modification support could provide support for the Atom Publishing Protocol.