There are dozens of list-making apps on the App Store, each of them designed to streamline the collation and organization of information. Some focus on packing as many features in as possible while others are all about style. Filing Cabinet Free for iPhone falls into the former camp, but does so with a limiting, poorly-crafted interface that makes the app hard to use.
When you open Filing Cabinet for iPhone, you'll be inside of an existing database that serves as a tutorial on how to use the app. The process is fairly easy but will take time depending on what you hope to get out of the app. For grocery lists and notes, it's easy to simply use one of the default templates, but to create another database and start adding entries, you'll be moving between menus near constantly trying to find the right buttons. The interface flips between portrait and landscape on occasion, the Help files are worded in difficult ways, and sharing or backing up information is much harder than it needs to be. While the app is very feature rich for a free tool, it is ultimately much too complicated for everyday use.
If you need a new list-creating and note-taking app that allows you to generate content in a flexible database, this is probably not the best app for your purposes. Keep looking for an app that will be more flexible and provide a better user interface for your needs.