iNaturalist.org is an amazing platform and resource for the global community to contribute, understand, and interact with the beauties, complexities, and dynamics of the living natural world.
I created a mobile-aimed webapp that supports quick semi-interactive browsing of abundant and popular iNaturalist observations throughout the planet, taking advantage of their fully featured web API:

This makes for a pretty fun experience, and a great alternative to constantly watching other ‘viral’ (and ad-based) apps.