AlternativeTo is a site I use quite a bit. Personally I use it when I get fed up with an Android app having too many ads / creepy network behavior or want to find a self-hostable version of a freemium service.
It has filters for free, open source, platform type, etc. From my understanding it’s all crowd sourced, so if you disagree with a rating put in a vote! Sharing this in hopes that others find it as useful as I do.
If you know of similar or better resources I would love to hear about them.
Edit: many people are noting that the comments and reviews are out of date. I agree! Despite that I still find it to he useful. It would be great if this little bit of visibility gets more folks engaged over there to improve it.
Happy to see it get love and spread the word. alternativeto.net is my go to. Worthy of muscle memory. I’ve also found great options in the awesome lists on github. Especially awesome self-hosted if we’re talking software. I thought I remember an alternativeto-like site geared towards cli, but I couldn’t find it last time I looked. LMK if that rings a bell for anyone.
Awesome Privacy is also great.
Swiso is also good. I don’t remember the URL right now