rate app

src/Android/Services/DeviceActionService.cs

@@ -261,6 +261,21 @@ namespace Bit.Droid.Services
             return result.Task;
         }
 
+        public void RateApp()
+        {
+            var activity = (MainActivity)CrossCurrentActivity.Current.Activity;
+            try
+            {
+                var rateIntent = RateIntentForUrl("market://details", activity);
+                activity.StartActivity(rateIntent);
+            }
+            catch(ActivityNotFoundException)
+            {
+                var rateIntent = RateIntentForUrl("https://play.google.com/store/apps/details", activity);
+                activity.StartActivity(rateIntent);
+            }
+        }
+
         private bool DeleteDir(Java.IO.File dir)
         {
             if(dir != null && dir.IsDirectory)
@@ -315,5 +330,22 @@ namespace Bit.Droid.Services
             }
             return intents;
         }
+
+        private Intent RateIntentForUrl(string url, Activity activity)
+        {
+            var intent = new Intent(Intent.ActionView, Android.Net.Uri.Parse($"{url}?id={activity.PackageName}"));
+            var flags = ActivityFlags.NoHistory | ActivityFlags.MultipleTask;
+            if((int)Build.VERSION.SdkInt >= 21)
+            {
+                flags |= ActivityFlags.NewDocument;
+            }
+            else
+            {
+                // noinspection deprecation
+                flags |= ActivityFlags.ClearWhenTaskReset;
+            }
+            intent.AddFlags(flags);
+            return intent;
+        }
     }
 }

src/App/Abstractions/IDeviceActionService.cs

@@ -16,5 +16,6 @@ namespace Bit.App.Abstractions
         Task SelectFileAsync();
         Task<string> DisplayPromptAync(string title = null, string description = null, string text = null,
             string okButtonText = null, string cancelButtonText = null);
+        void RateApp();
     }
 }

src/App/Pages/Settings/SettingsPage.xaml.cs

@@ -52,6 +52,10 @@ namespace Bit.App.Pages
             {
                 await _vm.FingerprintAsync();
             }
+            else if(item.Name == AppResources.RateTheApp)
+            {
+                _vm.Rate();
+            }
         }
     }
 }

src/App/Pages/Settings/SettingsPageViewModel.cs

@@ -1,4 +1,5 @@
-using Bit.App.Resources;
+using Bit.App.Abstractions;
+using Bit.App.Resources;
 using Bit.Core.Abstractions;
 using Bit.Core.Utilities;
 using System;
@@ -13,12 +14,14 @@ namespace Bit.App.Pages
         private readonly IPlatformUtilsService _platformUtilsService;
         private readonly ICryptoService _cryptoService;
         private readonly IUserService _userService;
+        private readonly IDeviceActionService _deviceActionService;
 
         public SettingsPageViewModel()
         {
             _platformUtilsService = ServiceContainer.Resolve<IPlatformUtilsService>("platformUtilsService");
             _cryptoService = ServiceContainer.Resolve<ICryptoService>("cryptoService");
             _userService = ServiceContainer.Resolve<IUserService>("userService");
+            _deviceActionService = ServiceContainer.Resolve<IDeviceActionService>("deviceActionService");
 
             PageTitle = AppResources.Settings;
             BuildList();
@@ -57,6 +60,11 @@ namespace Bit.App.Pages
             }
         }
 
+        public void Rate()
+        {
+            _deviceActionService.RateApp();
+        }
+
         private void BuildList()
         {
             var doUpper = Device.RuntimePlatform != Device.Android;

src/iOS/Services/DeviceActionService.cs

@@ -16,6 +16,7 @@ using Foundation;
 using MobileCoreServices;
 using Photos;
 using UIKit;
+using Xamarin.Forms;
 
 namespace Bit.iOS.Services
 {
@@ -197,6 +198,21 @@ namespace Bit.iOS.Services
             return result.Task;
         }
 
+        public void RateApp()
+        {
+            string uri = null;
+            if(SystemMajorVersion() < 11)
+            {
+                uri = "itms-apps://itunes.apple.com/WebObjects/MZStore.woa/wa/viewContentsUserReviews" +
+                    "?id=1137397744&onlyLatestVersion=true&pageNumber=0&sortOrdering=1&type=Purple+Software";
+            }
+            else
+            {
+                uri = "itms-apps://itunes.apple.com/us/app/id1137397744?action=write-review";
+            }
+            Device.OpenUri(new Uri(uri));
+        }
+
         private void ImagePicker_FinishedPickingMedia(object sender, UIImagePickerMediaPickedEventArgs e)
         {
             if(sender is UIImagePickerController picker)
@@ -313,5 +329,16 @@ namespace Bit.iOS.Services
             var documents = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
             return Path.Combine(documents, "..", "tmp");
         }
+
+        private int SystemMajorVersion()
+        {
+            var versionParts = UIDevice.CurrentDevice.SystemVersion.Split('.');
+            if(versionParts.Length > 0 && int.TryParse(versionParts[0], out int version))
+            {
+                return version;
+            }
+            // unable to determine version
+            return -1;
+        }
     }
 }