The best tools for migrating databases and applications to Oracle are Oracle SQL Developer Migration Workbench, SwisSQL, and Ispirer SQLWays. These tools automate the migration process, moving database objects like stored procedures and indexes. They can also migrate application SQL and proprietary database APIs. While some manual fixes are still needed, these tools have been around for a long time and provide high levels of automation. The migration of data and DDL can be highly automated, but system and user acceptance testing still require manual intervention due to varying use cases. Overall, these tools make the migration process smoother and more efficient.