diff --git a/MobileAuthApp/app/src/main/java/com/tarkvaraprojekt/mobileauthapp/auth/AuthAppException.kt b/MobileAuthApp/app/src/main/java/com/tarkvaraprojekt/mobileauthapp/auth/AuthAppException.kt
new file mode 100644
index 0000000..96b05d5
--- /dev/null
+++ b/MobileAuthApp/app/src/main/java/com/tarkvaraprojekt/mobileauthapp/auth/AuthAppException.kt
@@ -0,0 +1,10 @@
+package com.tarkvaraprojekt.mobileauthapp.auth
+
+/**
+ * A specialised RuntimeException class for exceptions related to the mobile authentication app.
+ * Possible error codes can be found at
+ * https://github.com/TanelOrumaa/Estonian-ID-card-mobile-authenticator-POC/wiki/Error-codes
+ * @param message Error message
+ * @param code An error code defined in the project wiki
+ */
+open class AuthAppException(message: String, var code: Int) : RuntimeException(message)
\ No newline at end of file
diff --git a/MobileAuthApp/app/src/main/java/com/tarkvaraprojekt/mobileauthapp/auth/InvalidCANException.kt b/MobileAuthApp/app/src/main/java/com/tarkvaraprojekt/mobileauthapp/auth/InvalidCANException.kt
new file mode 100644
index 0000000..073c790
--- /dev/null
+++ b/MobileAuthApp/app/src/main/java/com/tarkvaraprojekt/mobileauthapp/auth/InvalidCANException.kt
@@ -0,0 +1,7 @@
+package com.tarkvaraprojekt.mobileauthapp.auth
+
+/**
+ * An AuthAppException for when the user entered CAN does not match the one read from the ID-card
+ * @see AuthAppException
+ */
+class InvalidCANException : AuthAppException("Invalid CAN", 400)
\ No newline at end of file