Based on our record, File-Extensions.org seems to be more popular. It has been mentiond 1 time 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.
File-extensions.org lists following files for .3 extension:. Source: about 1 year ago
Publicfast - The first influencer marketing platform for Periscope
FileProInfo - It's All About Files, Software, Online Tools - 100% Free
Quuu Promote - Promote your content to influencers w/ curated content
FileInfo.com - FileInfo is the central file extensions registry and contains a database of over 10,000 file types.
Assmb.ly - Powered by intelligent technology, we’re delivering the content readers need, exactly when they need it, across four dynamic brands (and counting).
FILExt - Open, view and convert files online