XLFacility

XLFacility, which stands for Extensive Logging Facility, is an elegant and powerful logging facility for OS X & iOS. It was written from scratch with the following goals in mind:

• Drop-in replacement of NSLog() along with trivial to use macros to log messages anywhere in your app without impacting performance
• Support a wide variety of logging destinations aka “loggers”
• Customizable logging formats
• Modern, clean and compact codebase fully taking advantage of the latest Obj-C runtime and Grand Central Dispatch
• Easy to understand architecture with the ability to write custom loggers in a few lines of code
• No dependencies on third-party source code
• Available under a friendly New BSD License

Built-in loggers:

• Standard output and standard error
• Apple System Logger
• Local file
• Local SQLite database
• Telnet server which can be accessed from a terminal on a different computer to monitor log messages as they arrive
• HTTP server which can be accessed from a web browser on a different computer to browse the past log messages and see live updates
• Raw TCP connection which can send log messages to a remote server as they happen
• User interface logging window overlay for OS X & iOS apps