GetLatestVersion.cs

using Newtonsoft.Json;

public static async Task<Version> GetLatestVersion()
        {
            const string latestReleaseRequestUrl =
                @"https://api.github.com/repos/{user}/{repo}/releases/latest";

            try
            {
                string versionStr;
                using (var wc = new WebClient())
                {
                    wc.Headers.Add("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705;)");
                    versionStr = await wc.DownloadStringTaskAsync(latestReleaseRequestUrl);
                }
                var versionObj = JsonConvert.DeserializeObject<GithubRelease>(versionStr);
                return versionObj == null ? null : new Version(versionObj.TagName);
            }
            catch (Exception)
            {
            }
            return null;
        }