OtrosLogViewer (OLV) is software for analyzing an application's logs and stack traces. It loads logs from remote servers using ftp, sftp, ssh, samba and other supported filesystems, listening on a socket, or connection to a Log4j SocketHubAppender. Logs can be gzipped, and OLV will decompress them on the fly. Many log formats are supported (JDK logging, Log4j XML, and custom patterns). OLV allows log highlighting. Automatic log highlighting is based on string matches, regular expressions, or custom Java code. Notes can be added to log events. Display of message details can be customized by message formatters and a colorizer (i.e., formating SOAP request and highlighting XML syntax). OLV can be extended by plugins (filters, log parsers, log event markers, message detail formatters, and colorizers).