feat: If position is stale, show searching in UI

src/frontend/components/GpsPill.js

@@ -6,8 +6,14 @@ import { withNavigation, withNavigationFocus } from "react-navigation";
 import LocationContext from "../context/LocationContext";
 import GpsIcon from "./icons/GpsIcon";
 
-const GOOD_PRECISION = 10;
+// If the current position on the app state is more than 60 seconds old then we
+// consider it stale and show that the GPS is searching for a new position
+const STALE_TIMEOUT = 60 * 1000; // 60 seconds
+// If the precision is less than 10 meters then we consider this to be a "good
+// position" and we change the UI accordingly
+const GOOD_PRECISION = 10; // 10 meters
 const ERROR_COLOR = "#FF0000";
+
 const styles = StyleSheet.create({
   container: {
     flex: 0,
@@ -85,9 +91,12 @@ const ConnectedGpsPill = ({ navigation, isFocused }) => (
       const locationServicesDisabled =
         provider && !provider.locationServicesEnabled;
       const noPermission = permission && permission !== "granted";
+      const positionStale =
+        position && Date.now() - position.timestamp > STALE_TIMEOUT;
       let variant: Variant;
       if (error || gpsUnavailable || locationServicesDisabled || noPermission)
         variant = "error";
+      else if (positionStale) variant = "searching";
       else if (
         typeof precision === "number" &&
         Math.round(precision) <= GOOD_PRECISION