Module 6, Lesson 9: Testing on a Real Device

How do you test your app on a real Android phone with Claude Code? You connect the phone over USB, put it into USB debugging mode, and confirm the connection with ADB. Then you let Claude Code build a real dev build instead of relying on Expo Go, choose a USB connection over WiFi for stability, and walk the app yourself on the device the way an actual user would. The full walkthrough is in The Product Path.

What's the difference between testing in an emulator and testing on a real device?

An emulator confirms your app runs, but a real device confirms it runs the way a user will actually experience it: real network conditions, a real OS build, and a real touchscreen instead of a mouse click. In this lesson, testing on an actual Pixel phone surfaces a live connectivity error and an onboarding screen that hadn't shown up in emulator testing at all. Emulator testing is the first pass. Device testing is where you find out what the emulator was hiding.

Where We Are in the Course

Phase 1 closed out in the last lesson: identity, authentication, profile completion, and the co-parent invitation flow are all built and have been running in the Android emulator. This lesson is the next honest step before moving further into the build: get all of that running on an actual phone, not just the emulator, and see what breaks.

Before We Start

From previous lessons:

• Phase 1 (identity and relationships) is built and closed out, tested end to end in the emulator: sign-in, profile completion, and the co-parent invitation flow. Module 6, Lesson 8
• You've been testing exclusively in an Android emulator up to this point. Module 6, Lesson 4
• You know the pattern for starting Claude Code with an MCP config and letting it drive testing rather than narrating every step yourself. Module 6, Lesson 5

Tools / setup you'll need:

• An Android phone, with a USB cable to connect it to your computer
• USB debugging mode enabled on the phone (tap Build Number seven times under About Phone, then turn on USB debugging under Developer Options)
• ADB (Android Debug Bridge), installed and available on your machine
• Claude Code, connected to your project
• Your API and database running locally through Docker Compose, the same stack you've been using in emulator testing

By the end of this lesson, you'll:

• Have enabled USB debugging and confirmed your phone is visible over ADB
• Have had Claude Code build a real dev build for your device, instead of relying on Expo Go
• Have chosen a USB ADB connection over WiFi, and know why that choice matters
• Have walked sign-in and the start of onboarding on an actual phone
• Have caught a live connectivity error on-device and reported it back to Claude Code with a screenshot instead of a description

About This Lesson

Duration: ~7 minutes video
Skill Level: Intermediate
What You'll Build: Nothing new gets built here. This lesson is about proving what you already built in Phase 1 actually works on a real phone, not just an emulator.

This is a short lesson, and it's honest about being short: most of the setup is mechanical (USB debugging, ADB, choosing a connection type), and the real value is in what shows up once you're actually on the device. I hit a connectivity error mid-walkthrough that I hadn't seen in the emulator, and I catch an onboarding screen I hadn't noticed before either. That's the whole point of testing on a real device: it tells you things the emulator won't.