diff --git a/NAMESPACE b/NAMESPACE
index d891882..3fa2164 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -9,6 +9,7 @@ export(add_line)
 export(add_point)
 export(add_shade)
 export(add_shade_weekend)
+export(add_smooth_line)
 export(add_vline)
 export(aes)
 export(apex)
@@ -72,11 +73,15 @@ importFrom(htmlwidgets,shinyWidgetOutput)
 importFrom(htmlwidgets,sizingPolicy)
 importFrom(jsonlite,fromJSON)
 importFrom(magrittr,"%>%")
+importFrom(rlang,"!!")
 importFrom(rlang,as_label)
 importFrom(rlang,eval_tidy)
 importFrom(rlang,sym)
 importFrom(shiny,getDefaultReactiveDomain)
 importFrom(shiny,registerInputHandler)
 importFrom(shiny,shinyAppFile)
+importFrom(stats,lm)
+importFrom(stats,loess)
+importFrom(stats,predict)
 importFrom(stats,setNames)
 importFrom(utils,modifyList)
diff --git a/R/annotations.R b/R/annotations.R
index 6bde72c..95ad572 100644
--- a/R/annotations.R
+++ b/R/annotations.R
@@ -345,7 +345,7 @@ add_event_marker <- function(ax, when, y,
 #' @return An \code{apexcharts} \code{htmlwidget} object. 
 #' @export
 #' 
-#' @name add-lines
+#' @name add-vh-lines
 #'
 #' @example examples/add-lines.R
 add_hline <- function(ax, value, color = "#000", dash = 0, label = NULL, ...) {
@@ -362,7 +362,7 @@ add_hline <- function(ax, value, color = "#000", dash = 0, label = NULL, ...) {
   )
 }
 #' @export
-#' @rdname add-lines
+#' @rdname add-vh-lines
 add_vline <- function(ax, value, color = "#000", dash = 0, label = NULL, ...) {
   add_annotation(
     ax = ax, 
diff --git a/R/apex.R b/R/apex.R
index 982b704..857a7d9 100644
--- a/R/apex.R
+++ b/R/apex.R
@@ -95,6 +95,7 @@ apex <- function(data, mapping, type = "column", ...,
     )
   }
   ax$x$data <- data
+  ax$x$mapping <- mapping
   class(ax) <- c(class(ax), "apex")
   return(ax)
 }
diff --git a/R/apexcharter.R b/R/apexcharter.R
index 612a473..b332067 100644
--- a/R/apexcharter.R
+++ b/R/apexcharter.R
@@ -37,6 +37,7 @@ apexchart <- function(ax_opts = list(), auto_update = TRUE, width = NULL, height
     elementId = elementId,
     preRenderHook = function(widget) {
       widget$x$data <- NULL
+      widget$x$mapping <- NULL
       add_locale_apex(widget)
     },
     sizingPolicy = htmlwidgets::sizingPolicy(
diff --git a/R/mixed-charts.R b/R/mixed-charts.R
index c5248d0..5b5e155 100644
--- a/R/mixed-charts.R
+++ b/R/mixed-charts.R
@@ -1,5 +1,7 @@
 
-#' Add a line to a chart
+#' @title Add a line to a chart
+#' 
+#' @description On bar and scatter cherts add a line, on scatter charts add a smooth line.
 #'
 #' @param ax An \code{\link{apex}} \code{htmlwidget} object. 
 #' @param mapping Default list of aesthetic mappings to use for chart.
@@ -10,9 +12,15 @@
 #'
 #' @return A \code{apexcharts} \code{htmlwidget} object.
 #' @export
+#' 
+#' @name add-line
 #'
 #' @example examples/mixed-charts.R
-add_line <- function(ax, mapping, data = NULL, type = c("line", "spline"), serie_name = NULL) {
+add_line <- function(ax, 
+                     mapping, 
+                     data = NULL,
+                     type = c("line", "spline"), 
+                     serie_name = NULL) {
   type <- match.arg(type)
   if (!inherits(ax, "apex"))
     stop("add_line: ax must have been created with apex() function.", call. = FALSE)
@@ -47,7 +55,70 @@ add_line <- function(ax, mapping, data = NULL, type = c("line", "spline"), serie
       ax$x$ax_opts$stroke$width <- c(ax$x$ax_opts$stroke$width, 4)
     }
   }
+  if (identical(type, "line")) {
+    ax$x$ax_opts$stroke$curve <- "straight"
+  } else if (identical(type, "spline")) {
+    ax$x$ax_opts$stroke$curve <- "smooth"
+  }
   return(ax)
 }
 
 
+
+
+#' @param formula Formula passed to the \code{method}, default to \code{y ~ x} from main aesthetics.
+#' @param model Model to use between \code{\link{lm}} or \code{\link{loess}}.
+#' @param n Number of points used for predictions.
+#' @param ... Arguments passed to \code{model}.
+#' 
+#' @export
+#' 
+#' @importFrom stats lm loess predict
+#' @importFrom rlang !! sym
+#' 
+#' @name add-line
+add_smooth_line <- function(ax, 
+                            formula = y ~ x,
+                            model = c("lm", "loess"),
+                            n = 100,
+                            ...,
+                            type = c("line", "spline"),
+                            serie_name = NULL) {
+  model <- match.arg(model)
+  type <- match.arg(type)
+  if (!inherits(ax, "apex"))
+    stop("add_smooth_line: ax must have been created with apex() function.", call. = FALSE)
+  if (is.null(ax$x$mixed_type)) {
+    apex_type <- ax$x$ax_opts$chart$type
+    ax$x$mixed_type <- apex_type
+  } else {
+    apex_type <- ax$x$mixed_type
+  }
+  if (!isTRUE(apex_type %in% c("scatter")))
+    stop("add_smooth_line: apex() must be a scatter chart.", call. = FALSE)
+  ax$x$ax_opts$chart$type <- "line"
+  data <- as.data.frame(ax$x$data)
+  mapping <- ax$x$mapping
+  mapdata <- lapply(mapping, rlang::eval_tidy, data = data)
+  if (identical(model, "lm")) {
+    model_results <- lm(formula = formula, data = mapdata, ...)
+  } else if (identical(model, "loess")) {
+    model_results <- loess(formula = formula, data = mapdata, ...)
+  }
+  new_data <- data.frame(x = seq(
+    from = min(mapdata$x, na.rm = TRUE),
+    to = max(mapdata$x, na.rm = TRUE), 
+    length.out = n
+  ))
+  new_data$smooth <- predict(model_results, new_data)
+  add_line(
+    ax = ax,
+    mapping = aes(x = `!!`(sym("x")), y = `!!`(sym("smooth"))), 
+    data = new_data, 
+    type = type,
+    serie_name = serie_name
+  )
+}
+
+
+
diff --git a/examples/mixed-charts.R b/examples/mixed-charts.R
index d95f079..4e0899a 100644
--- a/examples/mixed-charts.R
+++ b/examples/mixed-charts.R
@@ -33,6 +33,25 @@ apex(cars, aes(speed, dist), type = "scatter") %>%
   add_line(aes(x, y), data = lowess(cars), serie_name = "lowess")
 
 
+# or directly
+apex(cars, aes(speed, dist), type = "scatter") %>% 
+  add_smooth_line()
+
+apex(cars, aes(speed, dist), type = "scatter") %>% 
+  add_smooth_line(model = "loess", span = 1)
+
+apex(cars, aes(speed, dist), type = "scatter") %>% 
+  add_smooth_line(model = "loess", degree = 1)
+
+
+apex(cars, aes(speed, dist), type = "scatter") %>% 
+  add_smooth_line(formula = y ~ poly(x, 2))
+
+apex(cars, aes(speed, dist), type = "scatter") %>% 
+  add_smooth_line(model = "lm", serie_name = "lm") %>% 
+  add_smooth_line(model = "loess", serie_name = "loess")
+
+
 
 
 
diff --git a/man/add_line.Rd b/man/add-line.Rd
similarity index 57%
rename from man/add_line.Rd
rename to man/add-line.Rd
index 65b1ed0..3da0969 100644
--- a/man/add_line.Rd
+++ b/man/add-line.Rd
@@ -1,7 +1,9 @@
 % Generated by roxygen2: do not edit by hand
 % Please edit documentation in R/mixed-charts.R
-\name{add_line}
+\name{add-line}
+\alias{add-line}
 \alias{add_line}
+\alias{add_smooth_line}
 \title{Add a line to a chart}
 \usage{
 add_line(
@@ -11,6 +13,16 @@ add_line(
   type = c("line", "spline"),
   serie_name = NULL
 )
+
+add_smooth_line(
+  ax,
+  formula = y ~ x,
+  model = c("lm", "loess"),
+  n = 100,
+  ...,
+  type = c("line", "spline"),
+  serie_name = NULL
+)
 }
 \arguments{
 \item{ax}{An \code{\link{apex}} \code{htmlwidget} object.}
@@ -23,12 +35,20 @@ the \code{data.frame} provided in \code{apex()} will be used.}
 \item{type}{Type of line.}
 
 \item{serie_name}{Name for the serie displayed in tooltip and legend.}
+
+\item{formula}{Formula passed to the \code{method}, default to \code{y ~ x} from main aesthetics.}
+
+\item{model}{Model to use between \code{\link{lm}} or \code{\link{loess}}.}
+
+\item{n}{Number of points used for predictions.}
+
+\item{...}{Arguments passed to \code{model}.}
 }
 \value{
 A \code{apexcharts} \code{htmlwidget} object.
 }
 \description{
-Add a line to a chart
+On bar and scatter cherts add a line, on scatter charts add a smooth line.
 }
 \examples{
 library(apexcharter)
@@ -66,6 +86,25 @@ apex(cars, aes(speed, dist), type = "scatter") \%>\%
   add_line(aes(x, y), data = lowess(cars), serie_name = "lowess")
 
 
+# or directly
+apex(cars, aes(speed, dist), type = "scatter") \%>\% 
+  add_smooth_line()
+
+apex(cars, aes(speed, dist), type = "scatter") \%>\% 
+  add_smooth_line(model = "loess", span = 1)
+
+apex(cars, aes(speed, dist), type = "scatter") \%>\% 
+  add_smooth_line(model = "loess", degree = 1)
+
+
+apex(cars, aes(speed, dist), type = "scatter") \%>\% 
+  add_smooth_line(formula = y ~ poly(x, 2))
+
+apex(cars, aes(speed, dist), type = "scatter") \%>\% 
+  add_smooth_line(model = "lm", serie_name = "lm") \%>\% 
+  add_smooth_line(model = "loess", serie_name = "loess")
+
+
 
 
 
diff --git a/man/add-lines.Rd b/man/add-vh-lines.Rd
similarity index 97%
rename from man/add-lines.Rd
rename to man/add-vh-lines.Rd
index 1227b41..a9f826d 100644
--- a/man/add-lines.Rd
+++ b/man/add-vh-lines.Rd
@@ -1,7 +1,7 @@
 % Generated by roxygen2: do not edit by hand
 % Please edit documentation in R/annotations.R
-\name{add-lines}
-\alias{add-lines}
+\name{add-vh-lines}
+\alias{add-vh-lines}
 \alias{add_hline}
 \alias{add_vline}
 \title{Add horizontal or vertical line}