https://fonts.google.com/specimen/Roboto (Android default Font - Apache 2.0 - Requires license and copyright notices to be present in copies of the software distributed)
Roboto is a neo-grotesque sans-serif typeface family developed by Google as the system font for its mobile operating system Android (Source)
https://fonts.google.com/specimen/Kanit (Open Font Licence - Same as above)
It is a combination of concepts, mixing a Humanist Sans Serif motif with the curves of Capsulated Geometric styles that makes it suitable for various uses, contemporary and futuristic (Source)
https://fonts.google.com/specimen/Roboto (Android default Font - Apache 2.0 - Requires license and copyright notices to be present in copies of the software distributed) Roboto is a neo-grotesque sans-serif typeface family developed by Google as the system font for its mobile operating system Android (Source)
https://fonts.google.com/specimen/Kanit (Open Font Licence - Same as above) It is a combination of concepts, mixing a Humanist Sans Serif motif with the curves of Capsulated Geometric styles that makes it suitable for various uses, contemporary and futuristic (Source)
https://fonts.google.com/specimen/Oxygen (Open Font Licence - Same as above) Oxygen is a sans-serif typeface family created as part of the KDE Project, a libre desktop for the GNU+Linux operating system (Source)