Simple Diary is a free note-taking app for Android developed by Tuxerito. It is a simple and easy-to-use application that allows you to jot down notes about your day.

The app comes with basic features such as password protection and the ability to create notes, defining categories, mood, and rating. You can also create and delete categories and notes. The app has a list of categories and a note list that can be filtered by category and month. It supports English and Spanish languages, and the notes are stored in the SD card.

One important feature of the app is that to view notes from other months, you need to press the ends of the pencil in the list notes screen. However, as this is the first version of the app, it has limited features and options.

Overall, Simple Diary is a basic note-taking app that is ideal for those who want a simple and easy-to-use app to jot down notes about their day without any frills or complicated features.