logstash - logstash is a tool for managing events and logs.
logit.io - Logit.io provides complete observability of logs, metrics and traces. The platform also offers alerting & monitoring, as well as Prometheus, OpenSearch & Grafana. Ingest any type of data to see real-time insights about your applications and services
rsyslog - Rsyslog is an enhanced syslogd supporting, among others, MySQL, PostgreSQL, failover log...
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Graylog - Graylog is an open source log management platform for collecting, indexing, and analyzing both structured and unstructured data.
Plumbr - Plumbr is an application performance platform that provides insights to users on the performance of their applications.