Watchtower - "Watchtower monitors your competition's websites and alerts you to important changes instantly."
Sygic Travel Maps - Itinerary planner for independent travelers
LaunchKit - Open Source - A popular suite of developer tools, now 100% open source.
Taab - Travel as a benefit™
Material Design for Bootstrap 4 - Powerful and free UI KIT for the newest Bootstrap 4 and Material Design
Tripsy - Planning your trip has gotten much easier.