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Consumer AI

AI-Powered Mobile Keyboard

On-device language intelligence for fast, private, multilingual typing.

Client
A consumer mobile brand
Sector
Consumer Mobile
Region
India · multilingual markets
Engagement
End-to-end build
On-device
Private inference
Multilingual
Personalised typing
TensorFlow Lite
Swift · Kotlin
01

The brief

Typing experiences in multilingual markets are hard: users switch scripts mid-sentence, transliterate freely, and expect instant suggestions. Cloud prediction was a non-starter for both latency and privacy.

The client wanted a keyboard whose intelligence ran entirely on the device: fast, private, and genuinely good at the mixed-language way people actually type.

What the client asked for
  • Deliver instant prediction and autocorrect suggestions on the phone.
  • Run entirely on-device. No text may ever leave the phone.
  • Handle multilingual, script-switching and transliterated typing naturally.
  • Personalise to each user locally, with no central data collection.
  • Adapt to each user's typing style over time.
  • Improve continuously for each user without compromising privacy.
02

Our AI-native approach

We built compact language models with TensorFlow Lite, quantised to run within a strict latency and memory budget on the device. The challenge was less raw modelling and more disciplined engineering: every millisecond and megabyte was measured.

Privacy was a design constraint, not a feature. Text never leaves the device, and personalisation happens locally.

03

What we built

01

On-device prediction

Next-word and correction models run locally with no network round-trip.

02

Multilingual & transliteration

Handles script-switching and romanised input the way users really type.

03

Local personalisation

The keyboard adapts to the user's vocabulary without sending it anywhere.

04

Smart autocorrect

Context-aware correction that respects mixed-language sentences.

05

Tiny footprint

Quantised models tuned to load fast and stay within memory budgets.

06

Privacy by default

No keystroke leaves the device; personalisation is fully local.

04

How we built it

This was a discipline problem more than a modelling one, so we built against a hard latency and memory budget from the first commit and measured every change against it. Models were quantised and pruned specifically for the target hardware tiers rather than shipped at full size.

We prototyped the transliteration path early, because it was the riskiest part of making typing feel natural, then hardened it. We owned on-device inference and the iOS and Android integrations, and we validated that personalisation happened entirely locally so no keystroke ever left the handset.

05

How it works

  1. Step 01

    Capture

    Keystrokes are processed entirely on device.

  2. Step 02

    Predict

    Compact TF Lite models score next-word and corrections.

  3. Step 03

    Adapt

    A local profile personalises suggestions over time.

  4. Step 04

    Render

    Suggestions surface within the latency budget.

  5. Step 05

    Forget

    No raw text is stored or transmitted off device.

The intelligence layer

The language models are quantised and pruned specifically for the target hardware, trading a sliver of accuracy for the responsiveness a keyboard demands. Transliteration is handled as a first-class path rather than bolted on, which is what makes mixed-script typing feel natural.

All learning is on-device, so the product improves for each user without any central data collection.

06

The impact

On-device
Private inference
Multilingual
Personalised typing
TensorFlow Lite
Swift · Kotlin

Suggestions arrive instantly because inference runs directly on the phone.

Mixed-language and transliterated typing worked the way users expect.

Privacy held as an architectural guarantee, not a policy promise.

Typing adapts to each user's style over time, across multiple languages.

07

Technology stack

Mobile
SwiftKotlinFirebase
On-device AI
TensorFlow LiteModel quantisationNLP
Engineering
Latency budgetingMemory profiling
Privacy
On-device inferenceLocal personalisation

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