restdb.io - restdb.io lets you create databases and REST APIs quickly. Development databases are free. Powerful web-based and mobile-friendly data management.
UserGuiding - Create in-app experiences with the most straightforward product adoption platform — quick implementation, lasting user engagement.
Firebase - Firebase is a cloud service designed to power real-time, collaborative applications for mobile and web.
Usetiful - Fight user churn with great user onboarding. Interactive product tours and smart tips significantly improve your user retention.
RemoteStorage - An open protocol for per-user storage OWN YOUR DATA
Userlane - Digital adoption platform with interactive guidance for software applications allowing anyone to understand and master any software from the get-go.