One metric, named up front
Before you join, the page tells you what will be shared, with whom, and between which two dates. Sharing ends automatically when the challenge ends; there is nothing to remember to switch off.
A challenge scores one thing: steps, weight, fasting, hydration, food, sleep, whichever it was set up for. Joining shares that metric with the other people in it and nothing else, for exactly as long as the challenge runs.

A challenge names a single number (steps, weight change, logging streak) and shows only that number to the people in it. Nothing else about your log travels with it.
Before you join, the page tells you what will be shared, with whom, and between which two dates. Sharing ends automatically when the challenge ends; there is nothing to remember to switch off.
A cumulative total, days you hit a goal, the longest streak, a daily average, percent change, or a combined score. Percent change shows only the percentage on the board, never anybody's actual weight.
Run it person against person, or split into teams scored on their sum or their average. A gym with four hundred members and a group of five friends use the same machinery.
Public to your community, invite-only with a join code, or fully private. The code is eight characters and works instantly for anybody already in your community.
Not everything needs a leaderboard. A buddy is one person who can see you are still turning up, which for most people is the accountability that actually works.
The board reads a computed score, never your raw entries. Rank movement is shown so a good week is visible even when you are not near the top.
Join an organization with its code and its contests are waiting for you. Same six scoring methods, same rule about what travels with you, run for the people you actually train beside.
An organization challenge is created by one of its admins and stays with its members. It is never published out to the wider Loopa community, and that is fixed rather than a box somebody can tick.
Nothing extra to type. You are already in the organization, so its challenges are simply on the list, and joining one is a tap.
Everyone in the organization can see which challenges are running, what each measures and when it ends. The leaderboard itself opens once you join it, because a daily health metric belongs to the people competing on it and not to the whole gym.
An admin can close a contest early and the results stand exactly as they were. Leave the organization and you come off anything still running, while scores you already posted stay on the board as history.
Organizations and their challenges are on the free tier. How organizations work
The metric the challenge is scored on, for the dates it runs, and your position. Not your food diary, not your weight unless weight is the metric, and nothing at all after it ends. On a percent-change challenge the board shows the percentage and never the underlying number.
At any time. You come off the leaderboard and the metric stops sharing at that moment.
No. Create it, get the join code, and send it to whoever you want. A challenge with one person in it is a commitment device, which is a legitimate way to use it.
Join the organization first, using the code your gym, club or employer gives you. Its challenges then appear on your list and you join one with a tap. There is no second code for the contest itself.
No. A challenge shares the one metric it is scored on, with the other people in it, for the dates it runs, and that is the same whether the challenge belongs to an organization or to four friends. Nobody in an organization can open your workouts, your food log, your weight, your measurements or your photos at all.
No, and the difference is the point. A challenge is scored and ranked. A buddy is one person who can see you are still showing up. Some people need a scoreboard and some need a witness.
Food, weight and water logging with 30 days of trends stays free. This is part of Premium.