This post is to answer a common question of why should we use the new feature Application Configuration Packages in App 9.
These are the advantages according to my point of view:
Group Custom Objects
Using Application configuration packages, it is possible to group several custom objects together and handle all those as a single unit. This is useful when there is a considerable large change, which involves several custom objects.
Handling as a single unit
Since application configuration packages can be exported and imported as a unit, this make administration much easier.
A version can be specified when exporting application configuration packages. Usually development work are carried out in development environment. Then it will be imported to a test environment and finally to production (live) environment.
Version information helps to identify the states of each environment, which helps in administration.
In application configuration package, it is possible to specify creator (owner) of the package. This helps to identify who did the changes and hence imposes security and also helps in proper change management concepts.