# Important challenge rules

Here are some important rules that govern the challenge process:

## Access to a challenge

A challenge can be configured for all users in a community or for a sub-group of users in the community. Only participants belonging to the group for which the challenge has been programmed will be able to access it.

## Registering for a challenge

A user must register for a challenge. Registration is not performed automatically.

## Challenge ranking

Two conditions must be validated for a user to be included in the challenge ranking. They are defined by :

1. a minimum number of trips
2. and a minimum distance

Users are not ranked until they have met the minimum challenge conditions. 

Participant ranking begins 24h00 after the start of the challenge.

Participant rankings cannot change after the end date of a challenge. If a trip made during a challenge is posted after the end date of the challenge, it will not be taken into account. For this reason, participants must ensure that their phone is connected to a mobile network.