Each station and log entry is stored within a category, to ease locating entries and keep things organized.
There is no cap on the number of categories you can create, within the limits imposed by the physical device (disk space and memory constraints).
The Edit button in the upper right of the category display view, when pressed, causes the standard red edit controls to appear next to each category. Tap that, and the Delete button will show.
If the category contains entries, you will be asked whether the program should delete them as well or move them. If you select "Move", they will be placed in the default category (which is created if it does not already exist).
The Edit button in the upper right of the category display view, when pressed, allows you to edit the categories. Tap the name of the category you wish to edit and the editor will appear.
If the category contains entries and you rename it to a name that already exists, the entries within will be moved into the destination category.
Every station or log entry is associated with a category, otherwise there would be no easy way to access it and it could be "lost" in your database.
Hence, any entry that doesn't have a category associated is dropped into the default category. When you install the application, this category is named "Unfiled". You can modify this behavior in the application setup.
If you only want to move a few entries to another category, edit them and set the category manually.
If there are many, or you want to move all the entries in one category to another, you can either delete the category and elect to move them to the default category or you can simply edit the category and rename it with the name of the destination where you want to move the entries to.
When viewing the contents of a category, tap the Edit button in the upper right corner. The standard red edit control will appear next to each entry. Tap that and the Delete button will show allowing you to remove the entry.