diff --git a/cores/arduino/WString.cpp b/cores/arduino/WString.cpp
index 380a8e5033..6c341f89c5 100644
--- a/cores/arduino/WString.cpp
+++ b/cores/arduino/WString.cpp
@@ -742,6 +742,11 @@ long String::toInt(void) const
 
 float String::toFloat(void) const
 {
-	if (buffer) return float(atof(buffer));
+	return float(toDouble());
+}
+
+double String::toDouble(void) const
+{
+	if (buffer) return atof(buffer);
 	return 0;
 }
diff --git a/cores/arduino/WString.h b/cores/arduino/WString.h
index 5618c0c574..3dd590d129 100644
--- a/cores/arduino/WString.h
+++ b/cores/arduino/WString.h
@@ -161,6 +161,10 @@ class String
 	void toCharArray(char *buf, unsigned int bufsize, unsigned int index=0) const
 		{getBytes((unsigned char *)buf, bufsize, index);}
 	const char * c_str() const { return buffer; }
+	char* begin() { return buffer; }
+	char* end() { return buffer + length(); }
+	const char* begin() const { return c_str(); }
+	const char* end() const { return c_str() + length(); }
 
 	// search
 	int indexOf( char ch ) const;
@@ -186,6 +190,7 @@ class String
 	// parsing/conversion
 	long toInt(void) const;
 	float toFloat(void) const;
+	double toDouble(void) const;
 
 protected:
 	char *buffer;	        // the actual char array