diff --git a/EnvelopeGenerator.ReceiverUI/Models/Constants/SenderAppType.cs b/EnvelopeGenerator.ReceiverUI/Models/Constants/SenderAppType.cs
new file mode 100644
index 00000000..f280c70a
--- /dev/null
+++ b/EnvelopeGenerator.ReceiverUI/Models/Constants/SenderAppType.cs
@@ -0,0 +1,8 @@
+namespace EnvelopeGenerator.ReceiverUI.Models.Constants
+{
+    public enum SenderAppType
+    {
+        LegacyFormApp = 0,
+        ReceiverUIBlazorApp = 1
+    }
+}
diff --git a/EnvelopeGenerator.ReceiverUI/Models/SignatureDto.cs b/EnvelopeGenerator.ReceiverUI/Models/SignatureDto.cs
index 2d90ebc3..dc8039b3 100644
--- a/EnvelopeGenerator.ReceiverUI/Models/SignatureDto.cs
+++ b/EnvelopeGenerator.ReceiverUI/Models/SignatureDto.cs
@@ -1,4 +1,6 @@
-namespace EnvelopeGenerator.ReceiverUI.Models;
+using EnvelopeGenerator.ReceiverUI.Models.Constants;
+
+namespace EnvelopeGenerator.ReceiverUI.Models;
 
 /// <summary>
 /// Represents a signature position on a PDF page.
@@ -19,4 +21,5 @@ public class SignatureDto
     /// <summary>1-based page number.</summary>
     public int Page { get; set; }
 
+    public SenderAppType SenderAppType { get; set; }
 }
\ No newline at end of file