Introduction to Mobile AI
What is Mobile AI?
“Mobile AI” means adding intelligent features — recognising images, understanding text, making predictions, generating content — to apps that run on phones. Some of this intelligence runs on the device itself (on-device AI), and some runs on powerful servers in the cloud that your app talks to. As a mobile developer, your job is to wire these capabilities into a smooth, fast, battery-friendly experience.
Where you already see it
- Face unlock and photo “people” grouping.
- Live translation, voice typing and smart replies.
- Camera effects, document scanning, QR detection.
- Recommendations, search ranking and spam filtering.
- Chat assistants and content generation (the new wave of generative AI).
The two big approaches
- On-device AI — the model runs locally. Fast, works offline, private (data never leaves the phone), but limited by the device’s memory and battery.
- Cloud AI — your app sends data to a server (or an API like OpenAI/Gemini), which runs a large model and returns the result. Far more powerful, but needs the internet, costs money per call, and sends user data off-device.
Most real apps use a mix: small tasks on-device, heavy tasks in the cloud. Choosing the right split is a core Mobile AI skill (covered in the next lesson).
The key vocabulary
- Model — a trained file that takes input (an image, text) and produces output (a label, a prediction).
- Inference — running the model to get a result (as opposed to training, which creates the model).
- Training — the (usually offline, data-science) process of teaching a model. Mobile devs mostly do inference, not training.
- Tensor — the numeric array format models use for input and output.
The mobile developer’s role
You usually don’t build models from scratch — data scientists or pre-trained models do that. Your job is to:
- Pick the right model or API for the feature.
- Get input ready (resize an image, clean up text).
- Run inference (on-device or via the cloud).
- Turn the raw output into a great UI — quickly and without draining the battery.
The toolkits you’ll meet
- TensorFlow Lite / LiteRT — on-device models on Android (and cross-platform).
- Core ML — on-device models on iOS.
- ML Kit — Google’s ready-made, high-level APIs (no model knowledge needed).
- Cloud AI APIs — Gemini, OpenAI and others for generative AI.
Common beginner misconceptions
- “I need a PhD in ML” — no; for most features you use pre-built models/APIs.
- “AI must run in the cloud” — modern phones run impressive models on-device.
- “Adding AI is just an API call” — the hard part is UX, performance, privacy and handling failure.
Summary: Mobile AI is about adding intelligent features to apps, either on-device (fast, private, offline) or via the cloud (powerful, online). You mostly run pre-trained models or APIs — your craft is choosing the right approach and delivering a fast, smooth, battery-friendly experience.