Unleash - Open source Feature toggle/flag service. Helps developers decrease their time-to-market and to increase learning through experimentation.
WP Remote - WP Remote provides a single place to monitor and update all of your WordPress sites.
Marvel for iOS - Rapid design and prototyping for the iPhone and iPad
Siterack - Automated website maintenance for WordPress.
Google Sites - Access Google Sites with a free Google account (for personal use) or G Suite account (for business use).
InfiniteWP - Manage unlimited https://alternativeto.net/software/wordpress/ sites from a central admin panel.