SorTea is simple, yet powerful system to help teachers to make evidence of lessons, maintain materials, easily reuse materials for future lessons and get statistical data for invoicing. As SorTea is desktop application with locally stored database, teachers are not dependent on more and more restrictive security politic of companies and schools regarding Wi-Fi access. However materials do not need to be stored locally, they can be maintain through application on shared disk or Google Drive which makes them accessible to students if applicable.
Do not delete "sorteadb" folder when upgrading, this is your database! :)