Clonk Rage, I’m not sure if this counts as it originally wasn’t open source, but it’s not developed further and the creator released the source code for all games of the Clonk franchise. Source: almost 2 years ago

F2P as it will never cost anything. Else anybody could add all freeware, Open Source, abandonware and shareware games. For example go to clonk.de and download all versions for free (except openclonk). Source: over 2 years ago

I am an OpenStreetMap enthusiast since 2013, before, I was very much involved in a PC game called OpenClonk (and before that Clonk) in my free time. Source: almost 3 years ago

No. You'll need a proper OSM editor for that. If you have Android have a look at Vespucci. I don't think there is anything similar for iOS. Source: 11 months ago

Vespucci (version 18.1.1.0): Edit geodata and contribute to OpenStreetMap project on-the-go. Source: over 1 year ago

I have found Vespucci app (https://vespucci.io/) to have latest data and edits. It would even highlight missing / incorrect attributes, which as a newbie, I found pretty useful. Source: over 1 year ago

And then there is Vespucci. As with JOSM, you can do almost everything, but this also makes it quite cumbersome to use. Source: over 1 year ago

You might be forced to use Vespucci or Every Door. Source: over 1 year ago