AWS CloudTrail - AWS CloudTrail is a web service that records AWS API calls for your account and delivers log files to you.
Graylog - Graylog is an open source log management platform for collecting, indexing, and analyzing both structured and unstructured data.
Logmatic - Logmatic is a log centralization, analytics & visualization platform to improve software & business performance.
Timber.io - Timber.io is the best logging platform for ruby, node, elixir and much more.
log4net - log4net is a tool to help the programmer output log statements to a variety of output targets.
Timber - Open source material design music player