By default the app will send a notification if the employees have not participated during the day. Depending on how the account was set up before sending the invitations, the notification alert would be sent accordingly: 

Nevertheless, the employees in the end adapt the notifications to their own preferences. The aim is not to force people to participate but to let them choose when they would like to receive a notification in case they forgot to do so during the day. Here is how in the app: 

Even so, if employees haven't participated in the last 7 days, they will receive another notification alerting to participate (this alert will be sent every 7 days without participating). If by any chance the employee doesn't participate during the last 30 days, we will send a notification and an email reminding them of the importance to participate. 

Or you can also send a more personalised email whenever you want in the dashboard: