Mergefly - A modern UI for GitHub pull requests
PullReminders - Review and release pull requests faster with Slack reminders and metrics.
Monolist.co - The command center for engineers. Tasks, pull requests, messages, docs — all in one place
Teamder - Tinder, but for creating teams at work.
PullRequest.com - Code review as a service
PR Chat - Manage and discuss Github PRs in Slack.