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Feature StoryAI · Look and logB by Lenskart

Nutrition on B, turning a glance at a plate into nutrition data

Buddy, the glasses' voice assistant, identifies a dish through the glasses camera, breaks down its nutrition and logs the meal by voice. The companion app keeps a Nutrition card with daily totals and meal history.

Product
B Glasses + appAjnaLens × Lenskart
Scope
Phase 12 user stories
Platforms
Android & iOSFigma · FigJam
Role
Design LeadUX · UI · voice
Nutrition on B, look at your plate, ask Buddy, and the meal is logged

01Overview

Nutrition is an AI feature on B Glasses. A user looks at their plate and asks Buddy "What's on my plate?" or says "Hey Buddy, log my meal!". Buddy identifies the dish through the glasses camera, breaks down its nutrition, and with the user's confirmation logs it to a Nutrition card in the companion app, with daily totals and history by date.

Phase 1 at a glance

2User stories
<5 sPerceived latency
11Values per meal
1 yrMeal history

02Where it started

The brief came as a Phase 1 PRD with three pieces to build: a look-and-tell answer to "What's on my plate?", a voice command to log a meal, and a Nutrition card in the app with daily totals, history by date, and delete.

The PRD named two goals, and every design decision had to serve both:

  • Visualise health insights. Close the gap between eating and knowing, using the camera and AI to give immediate, actionable data.
  • Increase glasses usage. Give people a daily, habit-forming reason to use the glasses beyond music and calls.

03The problem

Eating happens fast; knowing what you ate takes effort. On a phone, you search a food database, pick a portion and save. By then the meal is over, so most meals pass with no insight at all.

User problem

B Glasses users had no hands-free way to understand a meal before the first bite, or to keep a daily record without stopping to type.

Business problem

Glasses usage centred on music and calls. Without a daily, personal use case, there was little reason to talk to Buddy through the day.

How might we…

  1. Turn a glance at a plate into nutrition data in under 5 seconds?
  2. Keep users in control, so nothing is logged without their confirmation?
  3. Make meal logging a daily habit that brings users back to B Glasses?

04My role

I led Nutrition as design lead for B, working with the B design team of one UX and two UI designers. I owned the experience end to end, from reading the PRD to the screens and rules engineering built from.

  • Requirement review. Read the Phase 1 PRD against real use and mapped every requirement to a visible design response.
  • Discovery and scenario mapping. Scanned existing nutrition and smart-glasses experiences and mapped first-time and regular-user scenarios.
  • End-to-end user flow. One flow covering onboarding, the landing page, dates and delete, with every decision point.
  • UI design. The first-time experience, every state of the Nutrition landing page, meal detail, history and delete.

05Research and discovery

Discovery combined three things: a requirements review of the Phase 1 PRD, a scan of existing nutrition and smart-glasses experiences, and scenario mapping for first-time and regular users. The scan showed every current option breaks down at the same moment, the meal itself.

ApproachHow it worksGap
Manual phone trackersSearch a food database, choose portion, saveHigh effort per meal; easy to abandon
Phone-camera AI trackersSnap a photo with the phone for an estimatePhone must come out mid-meal
Glasses look-and-tellAsk the assistant what it seesAnswers, but no structured nutrients or history
B Glasses NutritionVoice + glasses camera + app cardHands-free capture, confirmed log, daily history

Insights that became design principles

01

Hands-free first

The meal is the moment. Capture starts with a voice command, not a phone.

02

Confirm, don't assume

Ask when an item is ambiguous, and never log without explicit consent.

03

Glanceable, not clinical

Lead with calories, then macros, then micros on demand.

04

Earn trust

Use exact brand data when known, and say clearly that values are AI-generated.

06Competitive landscape: direct and indirect

Food recognition from a photo is fast becoming a commodity. The real competition is over when capture happens, who stays in control, and what brings people back. That reframing shaped Phase 1 more than any single feature did.

How I mapped the market

I didn't want a feature checklist. I mapped competitors in two rings and judged each one through the same five questions a user lives through at the table:

01

Capture

Does the person have to stop eating to log?

02

Control

Who confirms what gets saved, the AI or the user?

03

Uncertainty

How does the product behave when it isn't sure?

04

Context

Does it understand a multi-dish Indian plate?

05

Return

What brings the person back tomorrow?

Direct competitors solve the same job on the same form factor: AI glasses that log food. Indirect competitors solve the same job another way: phone-camera AI trackers and manual logging apps. Our users already know these, so they set the bar for expectations.

Direct: AI glasses

Ray-Ban Meta and Oakley Meta. The closest benchmark. In April 2026 Meta announced food logging by voice prompt or quick photo, with Meta AI extracting nutrition details into a food log in the Meta AI app (9to5Google). It launched for US users aged 18+, and users still prompt Meta AI and set nutrition goals themselves; automatic logging is promised for later (Road to VR).

What it told me

Hands-free capture alone is not a moat. The global leader is moving the same way, so B has to win on the experience around capture: confirmation, clarification and local context.

Indirect: phone-camera AI trackers

ProductHow capture worksWhat stood out for design
HealthifyMe SnapPhone photo; trained on 150,000 Indian food items (TechCrunch)Built for Indian plates. With several items in one photo, users select and track each in an adjustable box (CXOToday)
MyFitnessPal Meal ScanHover the phone camera over the plateNot fully automatic: users confirm foods, portion and nutrition before saving (BrainStation)
Cal AIPhoto, barcode scan, or describe the meal in wordsSubscription model; acquired by MyFitnessPal in late 2025, a signal of how valuable photo logging has become (NeuronFeed)
What it told me

Every leader keeps a human confirmation step, which validated our "Confirm, don't assume" principle. And all of them still need the phone out mid-meal, which is exactly the moment B Glasses removes.

Indirect: manual logging

Classic trackers ask people to search a database, pick a portion and save. Even the photo-first apps market themselves against this: HealthifyMe says food tracking is hard to engage with because users have to type and remember to log (CXOToday).

Effort per meal is the churn driver.

Where B Glasses can win

QuestionPhone AI trackersMeta glassesB Glasses Nutrition
CapturePhone comes out mid-mealVoice or photo, hands-freeVoice + glasses camera, hands-free
ControlUser confirms in appUser prompts Meta AI to logBuddy confirms the dish by voice before saving
UncertaintyUser swipes alternatives or editsNot publicBuddy asks a follow-up ("milk or yogurt?"); AI-generated label on every view
Indian platesStrong in HealthifyMeUS launch firstDesigned around Indian dishes and branded snacks
ReturnDiary and goalsFood log in Meta AI appDaily Nutrition card and 1-year history; goals and trends are next
The decision

As a design lead, the decision this drove was simple. We would not compete on recognition accuracy, which belongs to the AI team and improves on its own. We would compete on the moment of capture and on trust, the two places design owns end to end.

07Users and scenarios

One feature, two very different users. Each meets Nutrition through a different moment, and the design had to answer different questions for each.

First-time user

Learn the feature quickly

  • What do I say, and when is Buddy listening?
  • What happens after the photo?
  • Where will I find my data?

Meets it throughThe two-page intro and Try Now, a guided first log

Regular user

A fast review of the day

  • How much have I eaten today, and of what?
  • What did I eat on a past date?
  • How do I remove a wrong log?

Meets it throughThe Nutrition landing page: daily totals, dates and meal detail

Two user stories, two voice moments

Story 4.1Meal photo breakdown
User

“What's on my plate?”or “How many calories are in this dish?”

Buddy
  1. Names at least 3 ingredients
  2. Gives calories, macros and micros
  3. Offers to log the meal
Story 4.2Log my meal
User

“Hey Buddy, log my meal!”

Buddy
  1. Confirms the dish by voice
  2. Replies with its nutrition
  3. Saves it to the Nutrition card by date
Why it matters

Both stories end with the user in control: 4.1 offers to log, 4.2 confirms before saving. Nothing reaches the Nutrition card without the user's say-so.

08Edge cases and constraints

A voice feature on a camera wearable fails in real-world ways a phone app never sees. Each one had a defined answer before build.

SituationHow it's handled
Ambiguous itemBuddy asks a follow-up, e.g. "Is this milk or yogurt?"
Branded snackExact brand data first, generic estimate second
Dirty lensUnclear image is treated as an edge case
Battery below 10%Feature unavailable
No Bluetooth or weak networkFeature needs both to work
Logout, then loginMeal history resyncs
Account deletedNutrition data is erased

09User flow

One flow covers both users. A returning-user check skips onboarding; date selection, empty states and deletion all branch off the Nutrition landing page.

End-to-end flow · entry, first-time onboarding, landing page, dates and delete
Nutrition user flow: start, tap Nutrition on B features card, returning user check, two-page intro carousel, Try Now or View Logged Meals, listening, glasses capture, analysing, insights explainer, Got it, Nutrition landing page, change date via calendar sheet, meals logged check, empty state or totals and meal list, meal detail, delete confirmation, end

Decision points

  • Returning user?
  • Which CTA tapped?
  • Change date?
  • Meals logged on date?
  • Confirm delete?

10First-time experience: teach the command, show the payoff

A new user has never spoken to their glasses about food. Five screens teach the exact phrase, show what the glasses are doing, and end on where the results will live.

  • Intro. A real meal moment and the exact phrase to say, with two paths: Try Now or View Logged Meals.
  • How it works. What the glasses and Buddy do after capture: photo, identification, nutrition estimate, and where to view it.
  • Listening. Speak after the tone; the LED blinks pink, so the glasses' state matches the screen.
  • Analysing. Sets expectations for the wait and points to the dashboard, where the status shows.
  • Where insights live. A preview of the landing page, closed with "Got it!"
Nutrition, Intro screen
Intro
Nutrition, How it works screen
How it works
Nutrition, Listening screen
Listening
Nutrition, Analysing screen
Analysing
Nutrition, Where insights live screen
Where insights live

11Nutrition landing page: every state of the day

The landing page is where a regular user spends their time, so every state of the day had to be clearly signalled.

StateWhat the user sees
Empty"Nothing on your plate yet" with the voice command in Buddy's gradient
AnalysingThe new meal appears as a processing row, so nothing blocks the user
LoggedCalories, then macros, then the meal list with time and calories
ExpandedView More reveals micronutrients; View Less folds them back
Nutrition, Empty state screen
Empty
Nutrition, Analysing state screen
Analysing
Nutrition, Logged state screen
Logged
Nutrition, Expanded state screen
Expanded

12Meal detail, history and delete

Review any day, correct any mistake.

  • Meal detail. Time, dish, calories, macros and micros for one meal; delete sits top right.
  • Pick a date. A calendar sheet with Cancel and Apply loads a past day.
  • Delete meal. A confirmation sheet explains that the meal's calories and nutrition data will be removed.
Nutrition, Meal detail screen
Meal detail
Nutrition, Pick a date screen
Pick a date
Nutrition, Delete meal screen
Delete meal

Date picker rules. Only dates up to today can be selected, future dates are disabled, and a dot marks days with logged meals. That gives five date states:

  • Active
  • Meal logged
  • Disabled
  • Selected
  • Today
Date statesdrop the image here
The five date states in the calendar sheet

13Key design decisions

Dark, calm interface

Matches the B Glasses app and keeps food photos and numbers in focus

Buddy's voice in gradient

Every voice prompt uses the same purple gradient, so users learn what to say

Progressive disclosure

Calories first, macros next, micros behind View More, so the screen stays glanceable

Visible system status

Listening, Analysing and Logged states mirror what the glasses are doing

Safe deletion

Delete always asks for confirmation and explains that nutrition data is removed

Honest about AI

Each nutrition view says values are AI-generated and may vary in accuracy

The biggest trade-off

Speed against control. Logging should feel instant, but a wrong log damages trust. So Buddy confirms the dish by voice before saving, and the Analysing row keeps the app usable while that happens.

14Requirements to design

Every PRD requirement has a visible answer in the experience.

PRD requirementDesign response
Image trigger: wake word + intent"Hey Buddy, log my meal" taught in onboarding; Listening screen and pink LED cue
Calories, macros and microsTotal intake card, macro row with icons, micronutrient list
Clarification dialogueBuddy asks a follow-up by voice; the exchange is saved as an AI transcript
Explicit confirmation before loggingBuddy confirms the dish by voice before the meal is saved
Perceived latency under 5 sAnalysing row in Your Meals keeps the app usable while processing
Meal logs by date, deletableDate chevron and calendar sheet; meal detail with delete confirmation
Branded snacksExact brand data takes priority over a generic estimate
Data deletion and resyncAccount deletion erases nutrition data; history returns after re-login

15Measuring success and next steps

What we'll track after launch

  • Meals logged per active user per week
  • Share of capture sessions that end in a confirmed log
  • Days per week a user talks to Buddy about food
  • Glasses sessions beyond music and calls
  • Meals deleted soon after logging, as an accuracy signal

Next steps, building on Phase 1

  • Usability test the first-time flow and voice prompts
  • Let users edit a dish or portion, not only delete it
  • Feed nutrition data into the upcoming Memory layer
  • Add daily goals and weekly trends to the Nutrition card
  • Show the clarification transcript inside meal detail

See your food. Know your food.

Sources

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