How StepFast works
StepFast compares your steps with a daily goal. If you're short, it shows what a walk would take. If you can't walk and fasting is on for you, it can suggest a later first meal instead.
1. Set up
You confirm you are 18 or older and enter your height and weight, in pounds or kilograms. There's no account to create. Apple Health is optional: allow it to read steps, weight and workouts, or enter steps yourself.
2. Your daily goal and zones
The app starts with an estimate of 5,000 steps a day and shows four zones around it: below, almost at, at, and above your goal. As you log steps and weigh-ins, StepFast can estimate the range of daily steps where your own weight holds steady. Some features, such as trends, are part of an optional paid tier; the App Store listing shows what is included.
3. If you're short on steps
StepFast turns the gap into something concrete. Walking comes first. At 100 steps a minute, every 1,000 steps is about 10 minutes of walking. On days you can't walk, and only if fasting is on for you, the app can instead suggest a later first meal: about 45 minutes later for each 1,000 steps short, never pushing total fasting past 18 hours in a day.
Try the step-gap math
4. Fasting is a choice, and a safety check comes first
Fasting is optional and off until you choose it. StepFast asks a few safety questions first and can keep fasting turned off for you. If you've told it about eating struggles, it doesn't push fasting. See who shouldn't fast.
5. Check in on trends
The app has four tabs: Today, Calculator, Fast and Trends. Today shows your steps and plan, Fast is the optional timer, and Trends shows your weight and steps over time.
Not medical advice. Fasting is not right for everyone. If you are under 18, pregnant or breastfeeding, have a history of disordered eating, or have a medical condition (especially diabetes or anything involving medication), talk to a doctor before fasting. Read the full safety page.