[Platform][pythonnative.Platform] is the canonical way to write platform-aware code:

import pythonnative as pn

font = pn.Platform.select(
    {"ios": "Helvetica", "android": "Roboto", "default": None}
)

if pn.Platform.is_ios:
    margin = 16
else:
    margin = 12

Platform.select looks up the current platform first, then "native" (matches iOS and Android), then "default", then the explicit default= argument. Platform.OS is "test" when running off-device, which is useful for skipping native-only code paths in tests.

PythonNative ships three reactive hooks that subscribe to the platform-published metrics in pythonnative.platform_metrics:

@pn.component
def Responsive():
    dims = pn.use_window_dimensions()
    insets = pn.use_safe_area_insets()
    keyboard = pn.use_keyboard_height()

    return pn.Column(
        pn.Text(f"{dims.width:.0f} × {dims.height:.0f}"),
        pn.Text(f"Bottom inset: {insets.bottom:.0f}"),
        pn.Text(f"Keyboard: {keyboard:.0f}"),
        style={"padding": 16, "spacing": 8},
    )

The component re-renders whenever the underlying value actually changes (no spurious renders on no-op updates). For most apps, [KeyboardAvoidingView][pythonnative.KeyboardAvoidingView] handles the keyboard case for you and you won't need [use_keyboard_height][pythonnative.use_keyboard_height] directly.

Mount [StatusBar][pythonnative.StatusBar] anywhere in the tree (it renders nothing visible) to control style and visibility:

pn.StatusBar(bar_style="light", background_color="#000000")

style is "light" (light icons, dark background), "dark" (dark icons, light background), or "default".

[Alert.show][pythonnative.alerts.Alert.show] is the imperative way to present a dialog. [Alert.confirm][pythonnative.alerts.Alert.confirm] wraps the common confirm/cancel case. The [Picker][pythonnative.Picker] component is implemented on top of Alert.show(style="action_sheet").

Every interactive component (Text, Button, Pressable, TextInput, Image, container views) accepts the same set of accessibility kwargs:

Components like [Button][pythonnative.Button] supply a sensible default accessibility_role for you.

accessibility_state mirrors React Native's prop of the same name. Supported keys are disabled, selected, checked, busy, and expanded; they map to UIAccessibilityTraits on iOS and to AccessibilityNodeInfo state on Android:

pn.Pressable(
    pn.Text("Inbox"),
    on_press=select_inbox,
    accessibility_role="button",
    accessibility_state={"selected": current_tab == "inbox"},
)

Set accessibility_live_region="polite" on a status line so screen readers announce its text when it changes without moving focus (use "assertive" only for content the user must hear immediately):

pn.Text(f"{unread} unread messages", accessibility_live_region="polite")

test_id gives UI-test frameworks (Maestro, Appium, XCUITest, Espresso) a stable handle that is independent of visible text. It maps to accessibilityIdentifier on iOS and to the accessibility node's viewIdResourceName (resource-id) on Android:

pn.Button("Continue", on_press=next_step, test_id="onboarding-continue")