Smoking-Log is an iPhone app developed by Kei Suefuji, designed to assist in smoking cessation by easily recording smoking habits. With a simple tap on the plus button, users can log the number of cigarettes smoked and the time of each smoking session. The app provides an "Analysis" screen that visually represents smoking frequency over weeks, months, and years, along with average daily consumption and smoking time intervals.

The "History" screen displays a calendar view of smoking times, allowing users to delete records with a tap. In the "Settings" section, users can customize the start day of the week on the calendar. The free version offers one week of smoking data, while the Pro version, available through in-app purchase, unlocks unlimited recordings and detailed monthly and yearly statistics.