Flinkit! - Web-hosted team building games for small and large companies
Streaks - The to-do list that helps you form good habits.
Social Games in Slack - Polly brings your WFH team together with interactive games
Taskful - Deadlines, meet your match.
Trivia for Google Chat - Team-building w/ fun quizzes, games right inside Google Chat
ToDoList - Windows desktop application to stay on top of your daily tasks.