Xamarin.Forms Getting Application and Device OS Version Numbers - Android & iOS - PCL


Example

The example below will collect the Device's OS version number and the the version of the application (which is defined in each projects' properties) that is entered into Version name on Android and Version on iOS.

First make an interface in your PCL project:

public interface INativeHelper {
    /// <summary>
    /// On iOS, gets the <c>CFBundleVersion</c> number and on Android, gets the <c>PackageInfo</c>'s <c>VersionName</c>, both of which are specified in their respective project properties.
    /// </summary>
    /// <returns><c>string</c>, containing the build number.</returns>
    string GetAppVersion();

    /// <summary>
    /// On iOS, gets the <c>UIDevice.CurrentDevice.SystemVersion</c> number and on Android, gets the <c>Build.VERSION.Release</c>.
    /// </summary>
    /// <returns><c>string</c>, containing the OS version number.</returns>
    string GetOsVersion();
}

Now we implement the interface in the Android and iOS projects.

Android:

[assembly: Dependency(typeof(NativeHelper_Android))]

namespace YourNamespace.Droid{
    public class NativeHelper_Android : INativeHelper {
        
        /// <summary>
        /// See interface summary.
        /// </summary>
        public string GetAppVersion() {
            Context context = Forms.Context;
            return context.PackageManager.GetPackageInfo(context.PackageName, 0).VersionName;
        }

        /// <summary>
        /// See interface summary.
        /// </summary>
        public string GetOsVersion() { return Build.VERSION.Release; }
    }
}

iOS:

[assembly: Dependency(typeof(NativeHelper_iOS))]

namespace YourNamespace.iOS {
    public class NativeHelper_iOS : INativeHelper {
        
        /// <summary>
        /// See interface summary.
        /// </summary>
        public string GetAppVersion() { return Foundation.NSBundle.MainBundle.InfoDictionary[new Foundation.NSString("CFBundleVersion")].ToString(); }

        /// <summary>
        /// See interface summary.
        /// </summary>
        public string GetOsVersion() { return UIDevice.CurrentDevice.SystemVersion; }
    }
}

Now to use the code in a method:

public string GetOsAndAppVersion {
    INativeHelper helper = DependencyService.Get<INativeHelper>();

    if(helper != null) {
        string osVersion  = helper.GetOsVersion();
        string appVersion = helper.GetBuildNumber()
    }
}