It's a full app built only with Xamarin Essentials features.

Description from Xamarin Essentials document:

Xamarin.Essentials provides several platform extension methods when having to work with platform types such as Rect, Size, and Point. This means that you can convert between the System version of these types for their iOS, Android, and UWP specific types.

Android Screen	iOS Screen	Description from Xamarin Essentials document
		The Connectivity class lets you monitor for changes in the device's network conditions, check the current network access, and how it is currently connected.
		The DeviceInfo class provides information about the device the application is running on.
		The Flashlight class has the ability to turn on or off the device's camera flash to turn it into a flashlight.
		The Geolocation class provides APIs to retrieve the device's current geolocation coordinates.
		The Magnetometer class lets you monitor the device's magnetometer sensor which indicates the device's orientation relative to Earth's magnetic field.
		The Preferences class helps to store application preferences in a key/value store.
		The TextToSpeech class enables an application to utilize the built-in text-to-speech engines to speak back text from the device and also to query available languages that the engine can support.
		The UnitConverters class provides several unit converters to help developers when using Xamarin.Essentials.
		The Launcher class enables an application to open a URI by the system. This is often used when deep linking into another application's custom URI schemes.

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Third-party packages used:
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