When building an app to manage SMS messages with the Vonage Messaging API, receiving inbound SMS messages is crucial. This tutorial explores how to receive SMS messages in real-time using Blazor and SignalR Core. To achieve this, developers need a Vonage API account, the latest .NET Core 3.1 SDK, and either Visual Studio 2019, Visual Studio for Mac, or Visual Studio Code. The app uses a controller to receive inbound SMS webhooks from Vonage, which are then sent to all clients connected to an SmsHub using SignalR. The frontend displays incoming messages in a table, and the app is tested with ngrok to create a publicly accessible URL. By combining SignalR, Blazor, and the Vonage APIs, developers can build an app that watches SMS messages come into real-time.