Mobile First Data Labelling for a Distributed AI Workforce

Three Hive Work screens on mobile: the job list, an explainer of the job types, and a categorization task in progress

How I redesigned a desktop-grade annotation tool for gig workers on low-end devices, cutting error rates by 60% and lifting task completion speed by 29%.

Mobile FirstAI ResearchAccessibilityData Labelling
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Error rate
↓ 60%
Completion speed
↑ 29%
Retention
↑ 22%
Workforce reach
6 markets

Overview

About the project

Hive Micro pays people to label the data that AI models train on: tagging objects in photographs, drawing boxes around them, transcribing audio. The tool was built for desktop, and most of the people doing the work have only a phone.

This is the redesign that moved it. It shipped on both stores, and the figures above are what moved with it: fewer misclassifications, faster tasks, and more workers coming back the following week.

Background

Who the work is for

The workforce spans Venezuela, El Salvador, Bolivia, the Indian subcontinent, Kenya and the Philippines. In most of it a phone is not the preferred device for online work, it is the only one.

The interface they met was a desktop annotation workflow shown on a small screen: touch targets sized for a cursor, zoom and precision controls that assumed a mouse, and dense instructions with no clear confirmation that a submission had landed.

That gap is not a polish problem. For many of these workers Hive Micro is not a side hustle, it is a lifeline, and a misclassification they cannot see coming costs them the task.

Approach

The Process

  1. Research

    Desk research and a competitor scan, mapping what mobile annotation already asked of workers.

  2. Synthesis

    Personas and an empathy map, built from worker testimonials rather than assumed profiles.

  3. Ideation

    Low and mid-fidelity concepts, worked against the constraints the research had surfaced.

  4. Final Designs

    High-fidelity screens, with the heaviest mobile interactions reworked around one-handed use.

  5. Reflection

    Results read against the error and completion rates the redesign set out to move.

Research

Key Findings

There was little to benchmark against — mobile annotation had almost no competitors — so the reading went into literature and worker testimonials instead. Three constraints came up in nearly all of it.

InsightDescriptionUX Opportunity

Fragmented attention

Work happens between chores, in short bursts.

Short, resumable interactions that survive an interruption.

Limited device resources

Entry-level phones on unstable, often prepaid networks.

A light UI, low data use, and state that saves itself.

Gesture familiarity

Pinch and swipe are already second nature.

Let gestures replace the on-screen controls duplicating them.

Research

What the interviews asked

Lightweight interviews with current and prospective mobile workers across Latin America, probing four things: what keeps someone working, what stops them, what their phone can bear, and what the money is for.

  • Motivation

    What brings someone back, and what the earnings actually pay for at home.

  • Finding work

    How hard it is to locate a task worth taking and get started on it.

  • Data and signal

    What a week of tasks costs in data, and how often the connection drops.

  • The device

    What phone the work happens on, and what it is shared with.

Synthesis

User Personas

Two personas carry the research, both drawn from testimonials rather than assumed profiles. They differ in the one dimension that changed the design most: whether the phone is a work device or a shared household one.

Oscar Mayenties

Oscar Mayenties

Oscar Mayenties

Seasonal event coordinator, Maracaibo, Venezuela

Age
29
Device
Android, 2GB
Peak season
4–5 months

Coordinates events around Carnival, Holy Week and the Christmas holidays. Outside those four or five months the income stops, and Hive Micro is what carries the gap. He works on shared Wi-Fi and public hotspots.

  • Goals

    • Hold $100 a week through the off-season
    • Build enough platform fluency for longer remote contracts
  • Pain Points

    • English-only task hints lead to misclassification
    • Instructions are hard to reach once a task has started
    • No sense of whether work was accepted, or when it pays
  • Behaviour

    • Works in concentrated bursts between seasonal contracts
    • Connects through shared Wi-Fi and hotspots in public spaces
  • Needs

    • Plain feedback on acceptance and payout timing
    • Tasks that queue offline and sync when signal returns
    • Spanish throughout, examples and tooltips included

Rossina Sanguinetti

Rossina Sanguinetti

Rossina Sanguinetti

Housewife and English Literature graduate, Mendoza, Argentina

Age
35
Device
Android, 3GB
Data
Prepaid, shared

Found Hive Micro through a Facebook group that shares remote work, and fits tasks around the household day. One prepaid phone carries both the work and the family messaging.

  • Goals

    • Contribute $50–80 a week to household costs
    • Build confidence with platforms that could lead to freelance work
  • Pain Points

    • Rejection or suspension arriving with no explanation
    • Eye strain across long annotation sessions
    • Submissions failing outright on weak mobile data
  • Behaviour

    • Works in short sessions fitted around the household
    • Shares one prepaid phone between work and family
  • Needs

    • Tasks that pause and resume across a dropped connection
    • Spanish instructions with worked examples
    • Visible confirmation that a submission landed
    • A light interface that loads fast on prepaid data

Constraint

One shared desktop, a phone each

Across low-income households in Bolivia, Venezuela and the Philippines the pattern repeats: a single desktop shared between everyone, and a personal smartphone for each of them, usually on prepaid data.

That settles the brief before any screen is drawn. Every critical task has to work on a 2–3GB Android phone, which rules out heavy loaders, full-resolution assets and background syncing that runs while nobody asked it to.

Delivery

The easy screens first

The task-interaction screens were the hard problem, so they were not the first problem. Ahead of them came everything around the task: sign-up and onboarding, the job list and the filters that cut it down, the coach marks that introduce it, and the practice tutorial that gates paid work.

Hive Micro already had a design system and a working web product, so these could go from Balsamiq wireframes straight to high fidelity, iterating with the data and engineering teams for feasibility and API alignment as they went.

The point was parallelism. Front-end development started on settled screens while research continued on the annotation flows, which bought engineering a two-week head start and bought the task screens the time they needed.

Balsamiq wireframes of the job dashboard and instruction screens, testing layout and hierarchy before visual designBalsamiq wireframes of the notification, scoreboard and modal surfaces

High fidelity

Getting in

Sign-up is the one screen every worker meets, and most of them meet it on a borrowed connection. It asks for three things and explains the fourth.

Three fields, and no more
Email, password, and an age check. Everything else the platform needs is asked for later, at the point there is a reason to ask.
Referral as a link, not a field
Most people arriving have no code, and an empty input that looks required is the commonest place a sign-up is abandoned. The code opens a field only for those who came with one.
Named before it is joined
A community of moderators using Hive to improve their lives, said in that many words above the form. Referral is worker-to-worker recruitment, so the copy states what is being joined rather than assuming it is known.
Two screens: sign-up with email, password, an age check and a referral link, and the referral code being typed under a short description of the community being joined

High fidelity

Teaching the work before the first task

Neither persona had heard of data labelling before finding the platform. Three cards explain it before a job is ever opened, and every one of them is skippable.

A definition in one sentence
Detecting and labelling samples of data — with the words a worker will meet again on every job card set in the accent colour, so they are recognised rather than re-learned.
A worked example, not a description
The job-type card draws a bounding box on a photograph instead of defining the term. The task is visual, so the explanation is too.
Skip stays on screen
Skip Tutorial sits top right of all three. Someone reinstalling on a new phone should not be made to read it a second time.
Two onboarding cards: What is Data Labeling, defining it in a sentence, and What are the different job types, showing a bounding box drawn on a photograph of a car

High fidelity

The first run on the job list

The list is the first screen carrying real density. It is introduced an element at a time, by coach marks that dismiss and do not come back.

The card explained on the card
The first mark points at a live job card and names what is on it: task type, pay per thousand tasks, and the approximate number of tasks left.
Qualification before disappointment
The second says that a job has to be qualified for before it pays. It is the rule that otherwise gets learned by being rejected.
One thing at a time
Three marks across three screens rather than one crowded overlay, each closing on an X, with the list underneath left usable throughout.
Two first-run screens: a coach mark naming the parts of a job card, and a second explaining that jobs must be qualified for before they pay

High fidelity

Finding work worth taking

Sixty-eight open jobs is more than anyone scrolls. Filtering is what turns the list into a shortlist, and it is the part of the redesign the research pointed at most directly.

Filters stay in sight
Applied filters remain on screen as removable chips above a live result count, so it is always visible why the list is as short as it is.
Job type, named not grouped
Bounding box, cuboid, keypoint, polygon, semantic segmentation, timestamp, audio transcription. This is the filter that decides whether a worker can do the job at all, so it gets a sheet of its own.
Language at the source
English-only task hints were Oscar's first pain point. Filtering to Español before a task is opened removes the misclassification instead of explaining it afterwards.
One panel to start over
The combined filter holds job type, task language and saved or qualified jobs behind a single Clear All, so a worker can reset without backing out of three sheets.

High fidelity

Qualifying before earning

Every job type has a practice tutorial that has to be passed before the paid version unlocks. It runs in the same interface as the real task, which is the point: nothing new is met at the moment the work starts counting.

Practice in the production screen
The tutorial uses the real annotation interface down to the header — 18 of 34 tasks, 15 correct to pass — so the threshold is known while it is being worked towards.
Answers explained on the spot
Right or wrong, the sheet names the correct answer immediately. Feedback arriving at the end of a set teaches nothing about the task that produced it.
An exit that states its cost
Quitting is confirmed, and the dialog says plainly what it costs: every unanswered task is marked incorrect.
A result, pass or fail
Completion shows accuracy and the earnings it unlocks. A failed attempt says so in the same layout rather than in an error state, because failing a practice test is an outcome and not a fault.

The hard part

Bounding boxes on a small screen

Categorization moved to mobile without much trouble. Bounding boxes did not: they ask someone to draw several rectangles accurately, pinch to zoom between them, and submit without a mistake, all on a screen a few inches wide.

The desktop original spent its space on a tri-panel productivity layout. A header carrying the job instructions, the task title and a persistent submit; a left panel holding a toggleable cheat sheet of examples and hints; the annotation canvas in the centre; and a right panel stacking pan, draw, zoom, focus, fit and undo alongside layer opacity and image settings. Almost none of that survives a phone.

The desktop bounding-box annotation screen: instructions and submit in the header, a cheat sheet panel to the left, the annotation canvas centre, and a dense tool cluster to the right

Iteration

The mobile interaction model

The first iteration split the screen into three zones, each with one job: explain the task, show the image, and finish it.

Header: context without a side panel
Task title, a Task 18 of 34 counter, and one-tap icons for instructions and the cheat sheet — the desktop header and left panel, folded into one bar.
Canvas: the full width, nothing on it
The image fills the width between the bars, letterboxed so any shape fits uncropped. The box is drawn straight onto it and adjusted by its handles.
Gestures instead of a tool panel
Pan, zoom and fit became gestures where one already existed; rarely used settings moved behind an overflow menu.
Bottom bar: every way a task ends
Add Box, Nothing to Bound and Submit, in one-handed thumb reach. Nothing to Bound records an empty image as an answer, not a skipped task.
Annotated first mobile iteration of a bounding-box task: a header with the task title, a Task 18 of 34 counter, and instruction and cheat sheet icons; a full-width canvas with a box drawn around a logo on a shoe; and a bottom bar with Add Box, Nothing to Bound and Submit

Outcome

Final Design

What the annotation screen settled into, once the controls stopped competing with the thing being annotated.

  • Vertical hierarchy

    Instructions, then image, then category — one decision per screenful.

  • Gesture-first canvas

    Auto-fit zoom and a gesture reset, with rare settings behind an overflow.

  • Real-time feedback

    Every action animates, so a submission is never silently in doubt.

  • Selective task types

    Semantic segmentation stays off mobile: the precision is not there.

Reflection

What it changed

Fewer errors
60%
Faster task completion
29%
More workers returning
22%

The redesign got there by phasing what shipped when, leaning on a design system that already existed, and refusing to move the hardest interaction until there was evidence for where it should go.

  • Clarity, not minimalism

    Constrained environments need things stated plainly, not fewer of them.

  • Parallel delivery

    Splitting easy screens from hard ones let design and engineering run at once.

  • Evidence-led iteration

    Task data settled the arguments that intuition alone kept reopening.

  • Selective annotation

    Some task types protect the worker better by not shipping to mobile.

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