Cal.com - Cal.com (formerly Calendso) is the open source Calendly alternative.
Planted - Planted is a mobile and online recruitment platform that matches recent graduates with non-technical roles at high-growth companies.
WhenWorks - Mobile appointment scheduling
SpringRole - A LinkedIn alternative on the blockchain
Inspora - virtual chat-stylist for fashion advice.
Sequoia One - Outsourced HR designed exclusively for high tech startups.