diff --git a/NAMESPACE b/NAMESPACE
index db4db95..62e8b3e 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -4,6 +4,11 @@ S3method(osem_measurements,bbox)
 S3method(osem_measurements,default)
 S3method(osem_measurements,sensebox)
 S3method(osem_phenomena,sensebox)
+S3method(plot,osem_measurements)
+S3method(plot,sensebox)
+S3method(print,sensebox)
+S3method(summary,sensebox)
+export(osem_as_sf)
 export(osem_box)
 export(osem_boxes)
 export(osem_counts)
diff --git a/R/api.R b/R/api.R
index 78c98fa..bad0c29 100644
--- a/R/api.R
+++ b/R/api.R
@@ -33,7 +33,6 @@ get_box_ = function (..., endpoint) {
 }
 
 get_measurements_ = function (..., endpoint) {
-  # FIXME: get rid of readr warnings
   result = httr::GET(endpoint, path = c('boxes', 'data'), query = list(...)) %>%
     httr::content(encoding = 'UTF-8') %>%
     osem_remote_error()
diff --git a/R/box_utils.R b/R/box_utils.R
index 2b6f3a2..41cf0ce 100644
--- a/R/box_utils.R
+++ b/R/box_utils.R
@@ -1,3 +1,4 @@
+#' @export
 plot.sensebox = function (x, ...) {
   # TODO: background map (maps::world), graticule?
   geom = x %>%
@@ -10,6 +11,7 @@ plot.sensebox = function (x, ...) {
   invisible(x)
 }
 
+#' @export
 print.sensebox = function(x, ...) {
   important_columns = c('name', 'exposure', 'lastMeasurement', 'phenomena')
   data = as.data.frame(x) # to get rid of the sf::`<-[` override..
@@ -18,37 +20,38 @@ print.sensebox = function(x, ...) {
   invisible(x)
 }
 
-summary.sensebox = function(x, ...) {
-  cat('boxes total:', nrow(x), fill = T)
+#' @export
+summary.sensebox = function(object, ...) {
+  cat('box total:', nrow(object), fill = T)
   cat('\nboxes by exposure:')
-  table(x$exposure) %>% print()
+  table(object$exposure) %>% print()
   cat('\nboxes by model:')
-  table(x$model) %>% print()
+  table(object$model) %>% print()
   cat('\n')
 
-  diffNow = (utc_date(Sys.time()) - x$lastMeasurement) %>% as.numeric(unit='hours')
-  neverActive = x[is.na(x$lastMeasurement), ] %>% nrow()
+  diffNow = (utc_date(Sys.time()) - object$lastMeasurement) %>% as.numeric(unit='hours')
+  neverActive = object[is.na(object$lastMeasurement), ] %>% nrow()
   list(
     'last_measurement_within' = c(
-      '1h' = nrow(x[diffNow <= 1, ]) - neverActive,
-      '1d' = nrow(x[diffNow <= 24, ]) - neverActive,
-      '30d' = nrow(x[diffNow <= 720, ]) - neverActive,
-      '365d' = nrow(x[diffNow <= 8760, ]) - neverActive,
+      '1h' = nrow(object[diffNow <= 1, ]) - neverActive,
+      '1d' = nrow(object[diffNow <= 24, ]) - neverActive,
+      '30d' = nrow(object[diffNow <= 720, ]) - neverActive,
+      '365d' = nrow(object[diffNow <= 8760, ]) - neverActive,
       'never' = neverActive
     )
   ) %>%
     print()
 
-  oldest = x[x$createdAt == min(x$createdAt), ]
-  newest = x[x$createdAt == max(x$createdAt), ]
+  oldest = object[object$createdAt == min(object$createdAt), ]
+  newest = object[object$createdAt == max(object$createdAt), ]
   cat('oldest box:', format(oldest$createdAt, '%F %T'), paste0('(', oldest$name, ')'), fill = T)
   cat('newest box:', format(newest$createdAt, '%F %T'), paste0('(', newest$name, ')'), fill = T)
 
   cat('\nsensors per box:', fill = T)
-  lapply(x$phenomena, length) %>%
+  lapply(object$phenomena, length) %>%
     as.numeric() %>%
     summary() %>%
     print()
 
-  invisible(x)
+  invisible(object)
 }
diff --git a/R/measurement_utils.R b/R/measurement_utils.R
index 33286b0..15757f0 100644
--- a/R/measurement_utils.R
+++ b/R/measurement_utils.R
@@ -1,3 +1,4 @@
+#' @export
 plot.osem_measurements = function (x, ...) {
   # TODO: group/color by sensor_id
   plot(value~createdAt, x, ...)
diff --git a/R/api_utils.R b/R/utils.R
similarity index 74%
rename from R/api_utils.R
rename to R/utils.R
index ef59c82..b226733 100644
--- a/R/api_utils.R
+++ b/R/utils.R
@@ -1,3 +1,14 @@
+#' Convert a \code{sensebox} or \code{osem_measurements} dataframe to an
+#' \code{\link[sf]{st_sf}} object.
+#'
+#' @param x The object to convert
+#' @param ... maybe more objects to convert
+#' @return The object with an st_geometry column attached.
+#' @export
+osem_as_sf = function (x, ...) {
+  sf::st_as_sf(x, ..., coords = c('lon', 'lat'), crs = 4326)
+}
+
 osem_remote_error = function (response) {
   suppressWarnings({
     hasCode = !is.null(response$code)
@@ -25,7 +36,3 @@ utc_date = function (date) {
 
 # NOTE: cannot handle mixed vectors of POSIXlt and POSIXct
 date_as_isostring = function (date) format(date, format = '%FT%TZ')
-
-osem_as_sf = function (x, ...) {
-  sf::st_as_sf(x, ..., coords = c('lon', 'lat'), crs = 4326)
-}