log4net - log4net is a tool to help the programmer output log statements to a variety of output targets.
AWS CloudTrail - AWS CloudTrail is a web service that records AWS API calls for your account and delivers log files to you.
Serilog - Backend Development and Utilities
Logary - Professional logging metrics and analytics for your apps
LOGBack - Logging framework
LogTailApp - LogTail is a local and remote (SSH) log file viewer and monitoring application for Mac OS X. It is a pure, modern, document-based Cocoa App