App Interface Guideline: Typography — Base Font Size. Keywords: fontScale dynamic type. Platform: iOS/Android/React Native. Description: Body text must be readable and support Dynamic Type. Do: Use platform fontScale and at least 14–16pt base. Don't: Render critical text below 12pt. Good Example: <Text style={{ fontSize: 16 }}>Body</Text>. Bad Example: <Text style={{ fontSize: 10 }}>Body</Text>. Severity: High.