That is a great initiative! I just installed the app and contributed some tweaks in my area.
Also, I couldn't find any info on this matter: some quests ask you what number a house is. Wouldn't people find it strange that a random person is standing in front of your house and looking at the number and then types on their smartphone?
AFAIK house numbers are not private info, but still...
Happens to me regularly, especially when I take photos of shop names, opening hour or draw building outlines (on an existing OSM map printout). The more residential the area the more questions. Of the last five questions two knew what OpenStreetMap is so that's progress.
I usually carry a few stickers on me just in case, so people can remember OSM and look it up later (after I explain what I'm doing and say it's a fun community project).
Also, I couldn't find any info on this matter: some quests ask you what number a house is. Wouldn't people find it strange that a random person is standing in front of your house and looking at the number and then types on their smartphone?
AFAIK house numbers are not private info, but still...