I made an Oracle APEX Plug-In that allows creating Slideover regions which slide in content from the side when opened.
Don't just hide Buttons when only some privileged users should be able to execute processes in Oracle APEX. With some JS you can still trigger them. Additionally use the read-only functionality where possible.
Great News: APEX 20.2 is finally out and adds a Dropzone component. For me, it does not look as intuitive as the Plug-In did, so I tried to improve the UX of it with a few lines of CSS.
If you use sequences to generate primary key values make sure you use the checksum feature of APEX. Otherwise, users can easily discover data they should not be able to see by raising or lowering the numeric ID in the URL.
Tables make it hard to give hierarchy to data. To underline the importance of certain values in a table you can use chips that highlight the values with colors.
I want to share a little script I wrote which generates a DML scripts for blob values like images. The output script can be used in your schema install script with your other master data.