Engine 1

• Clinical data, everyday language

  Units, mg/dL and insulin-to-carb ratios had to sit underneath a verdict anyone can understand mid-stride. Help tips explain terms like RPE in place.

• Time is the real axis

  Insulin peaks and fades. The UI had to show where you are now and where you will be in 30 minutes, all from one scroll gesture.

• Logging fatigue

  Blood glucose, insulin and food entries had to take seconds, or people stop doing them. A barcode scanner cuts food logging to a scan.

• One-handed, on the move

  Phones were getting bigger and people use this one while exercising, so the menu and log buttons moved to the bottom of the screen.

1. What is the single sentence someone needs before a workout?
2. Which everyday object makes insulin, food or water easy to read?
3. How few taps can it take to log a meal or a bolus?
4. What should the app say mid-run when glucose starts to drop?

A calm, dark onboarding sets up therapy type (pump or injections), long-acting insulin, body metrics and fitness level, so readiness forecasts are personal from the first session.

Sign-in, the intro and the Type 1 therapy check share one dark, calm palette.

The home screen answers one question. The verdict sits at the top, and the colour shifts from blue (go) to magenta (not recommended). Insulin on board, food to eat and food to carry update in real time as you scroll forward in time. The same state can be read as bubbles, a stacked timeline or concentric rings.

From "Perfect time" in blue to "Not recommended" in magenta.

The usual top-left hamburger moved to the bottom of the screen, beside the Workout and Log buttons. Tap or swipe right for the menu, swipe left to add a log. The sidebar carries the day's food, bolus and last glucose reading, plus caretakers, invites and the Pro plan.

Swipe right for the menu, left for a new log; both sit within thumb reach.

Simple forms log blood glucose, insulin and food with steppers and sliders. A barcode scanner reads food from certified vendors. The health log is a rack of colour-coded cards you pull out to see detail, and hydration fills a bottle.

BG and food forms either side of the colour-coded health-log rack.

The trendline shows everything on one time axis: food, insulin on board, blood glucose and workouts. The insulin-to-carb chart borrows from a traffic signal to show whether glucose is likely to rise or fall, with a scrubber to look ahead.

One time axis for glucose, insulin and food, and the traffic-signal IC ratio beside it.

Before a run, the workout screen pairs heart-rate monitors, offers live sharing and says what to eat now and what to carry. During it, a breadcrumb trail pins distance, glucose and carbs to the map, and a toggle switches to live BPM. A refuel prompt says how many grams of carbs to take before carrying on.

The breadcrumb map pins glucose and carbs to the route; the refuel prompt interrupts only when needed.

• Lead with the decision. The data is there to back it up, not to be read first.
• Borrow from real life. A bottle, a traffic signal and a rack of cards explained more than any chart legend.
• In health, colour is copy. Blue and magenta had to mean the same thing everywhere.