F-Droid is an app store for Android where only open source applications are available for free. It provides an alternative to the proprietary Google Play Store, which is where most Android app distribution currently takes place. Because the Google Play Store is where most users go to find and instal...
F-Droid is a software repository, not an app store. The distinction is subtle but important. A software repository offers a community-curated collection of software packages whereas an app store is just a marketplace for software developers to offer products to end-users. A software repository serves the interests of its community first, whereas an app store is merely a means for developers to sell products to end-users.
F-Droid is more of a marketplace for software developers than it is a set of community curated apps. The requirement for F-Droid software to be open source is just a guideline/rule like the minimum target API level on the Google Play Store. F-Droid is a neutral platform in my observations over the couple of years I have published there, and does not curate its content.
@trevor What are you talking about? If they can't build it themselves without proprietary stuff, then it doesn't get published. That's not a mere "guideline".
There are those who believe that F-Droid's role as a "middle man" vetting and building packages from source instead of blindly shipping builds provided by upstream makes it a security risk, because you're trusting F-Droid in addition to (some say instead of) the upstream developer. Perhaps telling is that none of these critics can offer an alternative solution.
Before anyone mentions Obtainium and Accrescent, these are not alternatives to F-Droid, they solve completely different problems.