Based on our record, Facebook Design Resources should be more popular than Stock Up. It has been mentiond 2 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Stockup - A new library filled with stock Images. Source: almost 2 years ago
Spotify isn't doing anything unique here, and it's not really a marketing campaign to explain away their UI. It's more of a showcase for hiring professionals, developers/designers/etc. Facebook has a similar one -> https://design.facebook.com/. Source: almost 3 years ago
Also, read anything published by Design @ Facebook. Source: over 3 years ago
Pexels - Find the best free stock images about Browser Home Page. Download all photos and use them even for commercial projects.
Designer Mill - Collection of Best Free Design Resources
Unsplash - Unsplash is a website with high-quality free HD images. It has a catalog of more than three hundred thousand striking images that are neatly organized with tags. Read more about Unsplash.
Interfacer - Collection of more than 200+ free design resources
StockSnap - Beautiful, free stock photos
Freebiesbug - Collection of the best free web design resources.