血糖値ノート is a free iPhone application designed for the intuitive recording of blood sugar measurements. It provides users with a visual representation of their blood sugar levels through facial icons, making it easier to understand their current health status. The app is particularly useful for individuals managing gestational diabetes (GDM) and those looking to prevent or treat diabetes by keeping track of their blood sugar results.

Key features include a customizable dashboard that displays average values and recent records, a calendar view for easy tracking of measurement dates, and trend graphs to visualize changes over time. Users can also export their data in PDF or Excel formats and share measurement records and graphs as images, facilitating communication with family members or healthcare providers during hospital stays.