Rain Log is a specialized iPhone application designed for users who want to manually track rainfall and snowfall data. The app allows users to easily record their measurements by simply double-tapping on a calendar date, entering the amount of precipitation, and saving the entry. It is important to note that Rain Log does not automatically fetch weather data from the internet; it relies solely on user input. This makes it an excellent tool for those who prefer or require manual tracking of their local weather conditions.

Key features of Rain Log include iCloud integration for seamless data sharing between devices, flexible measurement units (millimeters or inches), and the ability to add weather images and comments for each recorded date. Users can view monthly totals through a clear bar graph and compare current data with previous years. Additionally, the app offers backup options, including emailing data and saving to Dropbox in CSV format for easy importing into spreadsheets, ensuring that users can protect their valuable data.