A photo a day, for the people you pick. A room is a few people who each send at least one picture every day; your streak counts the days you kept it up. Today and yesterday show in the room; the pictures are kept.
It is a home-screen app for your phone. You get in with an invite link from whoever runs a room; the link signs you in with Google, shows you how to put the app on your home screen, and opens the room. Take a picture with the app (or both cameras at once), or send one from your roll, with a few words on it and, if you like, where you were.
Open your rooms if you already have been let in.
Photos and locations are visible to the room's members only. Nothing here is public. Run by one family on their own machine; no ads, nothing sold.