The easiest way of moving your database to another device is to make a backup of your current database in Menu > Backup.

eM Client will back up the whole application database into the folder selected in Menu > Settings > General > Backup. You can also enable the option of automatic backups in regular intervals here.

You can transfer this backup to a device of your choice and restore from it through Menu > File > Restore.

Read more in our blog: How to work with automatic backups in eM Client