diff --git a/DESCRIPTION b/DESCRIPTION
index d3b2471..f56655e 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -2,14 +2,13 @@ Package: opensensemap
 Type: Package
 Title: Work with Sensor Data from opensensemap.org in R
 Version: 0.1.0
-Imports: dplyr, httr
+Imports: dplyr, httr, magrittr
 Suggests: readr, sf
 Author: Norwin Roosen
 Maintainer: Norwin Roosen <noerw@gmx.de>
 Description: This packages ingests data (measurements, sensorstations) from the
-    API of opensensemap.org and transforms them into easy to use data.tables.
-    It uses the sf package for spatial handling of datapoints and aims to be
-    compatible with the tidyverse.
+    API of opensensemap.org for analysis in R.
+    The package aims to be compatible with sf and the tidyverse.
 License: GPL-2
 Encoding: UTF-8
 LazyData: true
diff --git a/NAMESPACE b/NAMESPACE
new file mode 100644
index 0000000..db4db95
--- /dev/null
+++ b/NAMESPACE
@@ -0,0 +1,13 @@
+# Generated by roxygen2: do not edit by hand
+
+S3method(osem_measurements,bbox)
+S3method(osem_measurements,default)
+S3method(osem_measurements,sensebox)
+S3method(osem_phenomena,sensebox)
+export(osem_box)
+export(osem_boxes)
+export(osem_counts)
+export(osem_measurements)
+export(osem_phenomena)
+importFrom(graphics,plot)
+importFrom(magrittr,"%>%")
diff --git a/R/api.R b/R/api.R
index 9cc1418..78c98fa 100644
--- a/R/api.R
+++ b/R/api.R
@@ -1,3 +1,9 @@
+# ==============================================================================
+#  getters for the opensensemap API.
+#  the awesome httr library does all the curling, query and response parsing.
+#  for CSV responses (get_measurements) the readr package is a hidden dependency
+# ==============================================================================
+
 # does not actually get called by the user. ... contains all the query parameters.
 # the proxy is just for parameter autocompletion, filtering out the endpoint
 get_boxes_ = function (..., endpoint) {
diff --git a/R/box.R b/R/box.R
new file mode 100644
index 0000000..2cd1fdd
--- /dev/null
+++ b/R/box.R
@@ -0,0 +1,125 @@
+# ==============================================================================
+#
+#' Get a set of senseBoxes from the openSenseMap
+#'
+#' Boxes can be selected by a set of filters.
+#' Note that some filters do not work together:
+#' \enumerate{
+#'   \item \code{phenomenon} can only be applied together with \code{date} or
+#'     \code{from / to}
+#'   \item \code{date} and \code{from / to} cannot be specified together
+#' }
+#'
+#' @param exposure Only return boxes with the given exposure ('indoor', 'outdoor', 'mobile')
+#' @param model Only return boxes with the given model
+#' @param grouptag Only return boxes with the given grouptag
+#' @param date Only return boxes that were measuring within ±4 hours of the given time
+#' @param from Only return boxes that were measuring later than this time
+#' @param to Only return boxes that were measuring earlier than this time
+#' @param phenomenon Only return boxes that measured the given phenomenon in the
+#'   time interval as specified through \code{date} or \code{from / to}
+#' @param endpoint The URL of the openSenseMap API instance
+#' @return A \code{sensebox data.frame} containing a box in each row
+#'
+#' @seealso \href{https://docs.opensensemap.org/#api-Measurements-findAllBoxes}{openSenseMap API documentation (web)}
+#' @seealso \code{\link{osem_phenomena}}
+#' @export
+#' @examples
+#' # TODO
+osem_boxes = function (exposure = NA, model = NA, grouptag = NA,
+                      date = NA, from = NA, to = NA, phenomenon = NA,
+                      endpoint = 'https://api.opensensemap.org') {
+
+  # error, if phenomenon, but no time given
+  if (!is.na(phenomenon) && is.na(date) && is.na(to) && is.na(from))
+    stop('Parameter "phenomenon" can only be used together with "date" or "from"/"to"')
+
+  # error, if date and from/to given
+  if (!is.na(date) && (!is.na(to) || !is.na(from)))
+    stop('Parameter "date" cannot be used together with "from"/"to"')
+
+  # error, if only one of from/to given
+  if (
+    (!is.na(to) && is.na(from)) ||
+    (is.na(to) && !is.na(from))
+  ) {
+   stop('Parameter "from"/"to" must be used together')
+  }
+
+  query = list(endpoint = endpoint)
+  if (!is.na(exposure)) query$exposure = exposure
+  if (!is.na(model)) query$model = model
+  if (!is.na(grouptag)) query$grouptag = grouptag
+  if (!is.na(phenomenon)) query$phenomenon = phenomenon
+
+  if (!is.na(to) && !is.na(from)) {
+    # error, if from is after to
+    # convert dates to commaseparated UTC ISOdates
+    query$date = parse_dateparams(from, to) %>% paste(collapse = ',')
+
+  } else if (!is.na(date)) {
+    query$date = utc_date(date) %>% date_as_isostring()
+  }
+
+  do.call(get_boxes_, query)
+}
+
+# ==============================================================================
+#
+#' Get a single senseBox by its ID
+#'
+#' @param boxId A string containing a senseBox ID
+#' @param endpoint The URL of the openSenseMap API instance
+#' @return A \code{sensebox data.frame} containing a box in each row
+#'
+#' @seealso \href{https://docs.opensensemap.org/#api-Measurements-findAllBoxes}{openSenseMap API documentation (web)}
+#' @seealso \code{\link{osem_phenomena}}
+#' @export
+#' @examples
+#' # TODO
+osem_box = function (boxId, endpoint = 'https://api.opensensemap.org') {
+  get_box_(boxId, endpoint = endpoint)
+}
+
+# ==============================================================================
+#
+#' Construct a senseBox data.frame
+#'
+#' Parses the fields of a \code{/boxes} response from the openSenseMap API
+#'
+#' @param boxdata A named \code{list} containing the data for a box
+#' @return A \code{data.frame} with an attached class \code{sensebox}.
+#' @noRd
+parse_senseboxdata = function (boxdata) {
+  # extract nested lists for later use & clean them from the list
+  # to allow a simple data.frame structure
+  sensors = boxdata$sensors
+  location = boxdata$loc
+  boxdata[c('loc', 'sensors', 'image', 'boxType')] <- NULL
+  thebox = as.data.frame(boxdata, stringsAsFactors = F)
+
+  # parse timestamps (updatedAt might be not defined)
+  thebox$createdAt = as.POSIXct(strptime(thebox$createdAt, format='%FT%T', tz = 'GMT'))
+  if (!is.null(thebox$updatedAt))
+    thebox$updatedAt = as.POSIXct(strptime(thebox$updatedAt, format='%FT%T', tz = 'GMT'))
+
+  # extract metadata from sensors
+  thebox$phenomena = list(unlist(lapply(sensors, function(s) { s$title })))
+  # FIXME: if one sensor has NA, max() returns bullshit
+  thebox$lastMeasurement = max(lapply(sensors, function(s) {
+    if (!is.null(s$lastMeasurement))
+      as.POSIXct(strptime(s$lastMeasurement$createdAt, format = '%FT%T', tz = 'GMT'))
+    else
+      NA
+  })[[1]])
+
+  # extract coordinates & transform to simple feature object
+  thebox$lon = location[[1]]$geometry$coordinates[[1]]
+  thebox$lat = location[[1]]$geometry$coordinates[[2]]
+  if (length(location[[1]]$geometry$coordinates) == 3)
+    thebox$height = location[[1]]$geometry$coordinates[[3]]
+
+  # attach a custom class for methods
+  class(thebox) = c('sensebox', class(thebox))
+  thebox
+}
diff --git a/R/box_api.R b/R/box_api.R
deleted file mode 100644
index dd127d8..0000000
--- a/R/box_api.R
+++ /dev/null
@@ -1,43 +0,0 @@
-`%>%` = magrittr::`%>%`
-
-osem_boxes = function (exposure = NA, model = NA, grouptag = NA,
-                      date = NA, from = NA, to = NA, phenomenon = NA,
-                      endpoint = 'https://api.opensensemap.org') {
-
-  # error, if phenomenon, but no time given
-  if (!is.na(phenomenon) && is.na(date) && is.na(to) && is.na(from))
-    stop('Parameter "phenomenon" can only be used together with "date" or "from"/"to"')
-
-  # error, if date and from/to given
-  if (!is.na(date) && (!is.na(to) || !is.na(from)))
-    stop('Parameter "date" cannot be used together with "from"/"to"')
-
-  # error, if only one of from/to given
-  if (
-    (!is.na(to) && is.na(from)) ||
-    (is.na(to) && !is.na(from))
-  ) {
-   stop('Parameter "from"/"to" must be used together')
-  }
-
-  query = list(endpoint = endpoint)
-  if (!is.na(exposure)) query$exposure = exposure
-  if (!is.na(model)) query$model = model
-  if (!is.na(grouptag)) query$grouptag = grouptag
-  if (!is.na(phenomenon)) query$phenomenon = phenomenon
-
-  if (!is.na(to) && !is.na(from)) {
-    # error, if from is after to
-    # convert dates to commaseparated UTC ISOdates
-    query$date = parse_dateparams(from, to) %>% paste(collapse = ',')
-
-  } else if (!is.na(date)) {
-    query$date = utc_date(date) %>% date_as_isostring()
-  }
-
-  do.call(get_boxes_, query)
-}
-
-osem_box = function (boxId, endpoint = 'https://api.opensensemap.org') {
-  get_box_(boxId, endpoint = endpoint)
-}
diff --git a/R/box_parse.R b/R/box_parse.R
deleted file mode 100644
index a3c937e..0000000
--- a/R/box_parse.R
+++ /dev/null
@@ -1,40 +0,0 @@
-parse_senseboxdata = function (boxdata) {
-  # extract nested lists for later use & clean them from the list
-  # to allow a simple data.frame structure
-  sensors = boxdata$sensors
-  location = boxdata$loc
-  boxdata[c('loc', 'sensors', 'image', 'boxType')] <- NULL
-  thebox = as.data.frame(boxdata, stringsAsFactors = F)
-
-  # parse timestamps (updatedAt might be not defined)
-  thebox$createdAt = as.POSIXct(strptime(thebox$createdAt, format='%FT%T', tz = 'GMT'))
-  if (!is.null(thebox$updatedAt))
-    thebox$updatedAt = as.POSIXct(strptime(thebox$updatedAt, format='%FT%T', tz = 'GMT'))
-
-  # extract metadata from sensors
-  thebox$phenomena = list(unlist(lapply(sensors, function(s) { s$title })))
-  # FIXME: if one sensor has NA, max() returns bullshit
-  thebox$lastMeasurement = max(lapply(sensors, function(s) {
-    if (!is.null(s$lastMeasurement))
-      as.POSIXct(strptime(s$lastMeasurement$createdAt, format = '%FT%T', tz = 'GMT'))
-    else
-      NA
-  })[[1]])
-
-  # extract coordinates & transform to simple feature object
-  thebox$lon = location[[1]]$geometry$coordinates[[1]]
-  thebox$lat = location[[1]]$geometry$coordinates[[2]]
-  if (length(location[[1]]$geometry$coordinates) == 3)
-    thebox$height = location[[1]]$geometry$coordinates[[3]]
-
-  # attach a custom class for methods
-  class(thebox) = c('sensebox', class(thebox))
-  thebox
-}
-
-get_phenomena = function (x, ...) UseMethod('get_phenomena')
-get_phenomena.default = function (x, ...) stop('not implemented')
-get_phenomena.sensebox = function (x, ...) {
-  # FIXME: only returns first box for get_boxes!
-  x$phenomena[[1]]
-}
diff --git a/R/box_utils.R b/R/box_utils.R
index a591f61..2b6f3a2 100644
--- a/R/box_utils.R
+++ b/R/box_utils.R
@@ -1,5 +1,3 @@
-`%>%` = magrittr::`%>%`
-
 plot.sensebox = function (x, ...) {
   # TODO: background map (maps::world), graticule?
   geom = x %>%
@@ -16,6 +14,7 @@ print.sensebox = function(x, ...) {
   important_columns = c('name', 'exposure', 'lastMeasurement', 'phenomena')
   data = as.data.frame(x) # to get rid of the sf::`<-[` override..
   print(data[important_columns], ...)
+
   invisible(x)
 }
 
@@ -27,7 +26,7 @@ summary.sensebox = function(x, ...) {
   table(x$model) %>% print()
   cat('\n')
 
-  diffNow = (utc_time(Sys.time()) - x$lastMeasurement) %>% as.numeric(unit='hours')
+  diffNow = (utc_date(Sys.time()) - x$lastMeasurement) %>% as.numeric(unit='hours')
   neverActive = x[is.na(x$lastMeasurement), ] %>% nrow()
   list(
     'last_measurement_within' = c(
@@ -53,12 +52,3 @@ summary.sensebox = function(x, ...) {
 
   invisible(x)
 }
-
-osem_phenomena = function (x) UseMethod('osem_phenomena')
-osem_phenomena.default = function (x) stop('not implemented')
-osem_phenomena.sensebox = function (x) {
-  Reduce(`c`, x$phenomena) %>% # get all the row contents in a single vector
-    table() %>%                # get count for each phenomenon
-    t() %>%                    # transform the table to a df
-    as.data.frame.matrix()
-}
diff --git a/R/counts.R b/R/counts.R
new file mode 100644
index 0000000..6636b1f
--- /dev/null
+++ b/R/counts.R
@@ -0,0 +1,16 @@
+# ==============================================================================
+#
+#' Get count statistics of the openSenseMap Instance
+#'
+#' Provides information on number of senseBoxes, measurements, and measurements per minute.
+#'
+#' @details Note that the API caches these values for 5 minutes.
+#'
+#' @param endpoint The URL of the openSenseMap API
+#' @return A named \code{list} containing the counts
+#'
+#' @export
+#' @seealso \href{https://docs.opensensemap.org/#api-Misc-getStatistics}{openSenseMap API documentation (web)}
+osem_counts = function (endpoint = 'https://api.opensensemap.org') {
+  get_stats_(endpoint)
+}
diff --git a/R/counts_api.R b/R/counts_api.R
deleted file mode 100644
index fc2e80d..0000000
--- a/R/counts_api.R
+++ /dev/null
@@ -1,3 +0,0 @@
-osem_counts = function (endpoint = 'https://api.opensensemap.org') {
-  get_stats_(endpoint)
-}
diff --git a/R/measurement_api.R b/R/measurement.R
similarity index 55%
rename from R/measurement_api.R
rename to R/measurement.R
index 249e192..b4d172f 100644
--- a/R/measurement_api.R
+++ b/R/measurement.R
@@ -6,6 +6,14 @@
 #' bounding box filter. To get all measurements, the \code{default} function applies
 #' a bounding box spanning the whole world.
 #'
+#' @param x Depending on the method, either
+#'   \enumerate{
+#'     \item a \code{chr} specifying the phenomenon, see \code{phenomenon}
+#'     \item a \code{\link[sf]{st_bbox}} to select sensors spatially,
+#'     \item a \code{sensebox data.frame} to select boxes from which
+#'       measurements will be retrieved,
+#'   }
+#' @param ... see parameters below
 #' @param phenomenon The phenomenon to retrieve measurements for
 #' @param exposure Filter sensors by their exposure ('indoor', 'outdoor', 'mobile')
 #' @param from A \code{POSIXt} like object to select a time interval
@@ -13,102 +21,79 @@
 #' @param columns Select specific column in the output (see oSeM documentation)
 #' @param endpoint The URL of the openSenseMap API
 #'
-#' @return An \code{osem_measurements} \code{data.frame} containing the
+#' @return An \code{osem_measurements data.frame} containing the
 #'   requested measurements
 #'
 #' @export
-#' @family osem_measurements
-#' @seealso \href{https://docs.opensensemap.org/#api-Measurements-getDataMulti}{openSenseMap API documentation}
+#' @seealso \href{https://docs.opensensemap.org/#api-Measurements-getDataMulti}{openSenseMap API documentation (web)}
+#' @seealso \code{\link{osem_boxes}}
 osem_measurements = function (x, ...) UseMethod('osem_measurements')
 
 # ==============================================================================
 #
-#' Get the Measurements of a Phenomenon from all sensors
-#'
-#' @param ... Passed on to \code{\link{osem_measurements.bbox}}
-#' @inherit osem_measurements seealso return
-#' @inheritParams osem_measurements
-#'
+#' @describeIn osem_measurements Get measurements from \strong{all} senseBoxes.
 #' @export
-#' @family osem_measurements
-#' @seealso \code{\link{osem_measurements.bbox}}
-#' @seealso \href{https://docs.opensensemap.org/#api-Measurements-getDataMulti}{openSenseMap API documentation}
-#'
 #' @examples
+#' # get measurements from all boxes
+#' \dontrun{
 #' osem_measurements('PM2.5')
-osem_measurements.default = function (phenomenon, ...) {
+#' }
+#'
+osem_measurements.default = function (x, ...) {
   bbox = structure(c(-180, -90, 180, 90), class = 'bbox')
-  osem_measurements(bbox, phenomenon, ...)
+  osem_measurements(bbox, x, ...)
 }
 
 # ==============================================================================
 #
-#' Get the Measurements of a Phenomenon by a spatial filter
-#'
-#' @param bbox A \code{\link[sf]{st_bbox}} to select sensors spatially
-#' @inheritParams phenomenon,exposure,from,to,columns,endpoint osem_measurements
-#'
-#' @return An \code{osem_measurements} \code{data.frame} containing the
-#'   requested measurements
-#'
+#' @describeIn osem_measurements Get measurements by a spatial filter.
 #' @export
-#' @family osem_measurements
-#' @seealso \href{https://docs.opensensemap.org/#api-Measurements-getDataMulti}{openSenseMap API documentation}
-#' @seealso \code{\link[sf]{st_bbox}}
-#'
 #' @examples
-#' bbox = structure(c(7.5, 51, 8, 52), class = 'bbox')
-#' osem_measurements(bbox, 'Temperature')
+#' # get measurements from sensors within a bounding box
+#' bbox = structure(c(7, 51, 8, 52), class = 'bbox')
+#' osem_measurements(bbox, 'Temperatur')
 #'
+#' points = sf::st_multipoint(x = matrix(c(7,8,51,52),2,2))
+#' bbox2 = sf::st_bbox(points)
+#' osem_measurements(bbox2, 'Temperatur', exposure = 'outdoor')
 #'
-#' bbox2 = sf::st_point(c(7, 51)) %>% sf::st_bbox()
-#' osem_measurements(bbox2, 'Temperature', exposure = 'outdoor')
-osem_measurements.bbox = function (bbox, phenomenon, exposure = NA,
-                                   from = NA, to = NA,
-                                   columns = NA,
+osem_measurements.bbox = function (x, phenomenon, exposure = NA,
+                                   from = NA, to = NA, columns = NA,
+                                   ...,
                                    endpoint = 'https://api.opensensemap.org') {
+  bbox = x
   query = parse_get_measurements_params(as.list(environment()))
   do.call(get_measurements_, query)
 }
 
 # ==============================================================================
 #
-#' Get the Measurements of a Phenomenon for a set of senseBoxes
-#'
-#' @param boxes A \code{sensebox} \code{data.frame} to select boxes from which
-#'   measurements will be retrieved
-#' @inheritParams phenomenon,exposure,from,to,columns,endpoint osem_measurements
-#'
-#' @return An \code{osem_measurements} \code{data.frame} containing the
-#'   requested measurements
-#'
+#' @describeIn osem_measurements Get measurements from a set of senseBoxes.
 #' @export
-#' @family osem_measurements
-#' @seealso [osem_boxes()]
-#' @seealso [osem_box()]
-#'
 #' @examples
-#' osem_boxes(grouptag = 'ifgi') %>% get_measurements(phenomenon = 'Temperatur')
+#' # get measurements from a set of boxes
+#' b = osem_boxes(grouptag = 'ifgi')
+#' osem_measurements(b, phenomenon = 'Temperatur')
 #'
+#' # ...or a single box
 #' b = osem_box('593bcd656ccf3b0011791f5a')
-#' get_measurements(b, phenomenon = 'Temperatur')
-osem_measurements.sensebox = function (boxes, phenomenon, exposure = NA,
-                                       from = NA, to = NA,
-                                       columns = NA,
+#' osem_measurements(b, phenomenon = 'Temperatur')
+#'
+osem_measurements.sensebox = function (x, phenomenon, exposure = NA,
+                                       from = NA, to = NA, columns = NA,
+                                       ...,
                                        endpoint = 'https://api.opensensemap.org') {
+  boxes = x
   query = parse_get_measurements_params(as.list(environment()))
   do.call(get_measurements_, query)
 }
 
 # ==============================================================================
 #
-#' Validates and parses the Parameters for \code{osem_measurements()}
+#' Validates and parses the Parameters for use in \code{osem_measurements()}
 #'
 #' @param params A named \code{list} of parameters
-#'
 #' @return A named \code{list} of parsed parameters.
-#'
-#' @family osem_internal
 #' @noRd
 parse_get_measurements_params = function (params) {
   if (is.null(params$phenomenon) | is.na(params$phenomenon))
diff --git a/R/measurement_utils.R b/R/measurement_utils.R
index 5236d2b..33286b0 100644
--- a/R/measurement_utils.R
+++ b/R/measurement_utils.R
@@ -1,15 +1,3 @@
-#' Plot openSenseMap Measurements by Time & Value
-#'
-#' @param x An \code{osem_measurements} \code{data.frame}.
-#' @param ... Any parameters you would otherwise pass to \code{plot.formula}.
-#'
-#' @return The input data is returned
-#' @export
-#'
-#' @examples
-#' osem_boxes(grouptag = 'ifgi') %>%
-#'   osem_measurements(phenomenon = 'Temperatur') %>%
-#'   plot()
 plot.osem_measurements = function (x, ...) {
   # TODO: group/color by sensor_id
   plot(value~createdAt, x, ...)
diff --git a/R/opensensemap.R b/R/opensensemap.R
new file mode 100644
index 0000000..7fa96aa
--- /dev/null
+++ b/R/opensensemap.R
@@ -0,0 +1,29 @@
+#' opensensemap: Work with sensor data from opensensemap.org
+#'
+#' The opensensemap package provides three categories functions:
+#' \enumerate{
+#'   \item retrieval of senseBoxes
+#'   \item retrieval of measurements
+#'   \item general stats about the opensensemap database
+#' }
+#'
+#' @section Retrieving senseBox metadata:
+#' TODO
+#'
+#' @section Retrieving measurements:
+#' TODO
+#'
+#' @section Retrieving statistics:
+#' TODO
+#'
+#' @section Working with spatial data from openSenseMap:
+#' TODO
+#'
+#' @docType package
+#' @name opensensemap
+'_PACKAGE'
+
+#' @importFrom graphics plot
+
+#' @importFrom magrittr %>%
+`%>%` = magrittr::`%>%`
diff --git a/R/phenomena.R b/R/phenomena.R
new file mode 100644
index 0000000..182710c
--- /dev/null
+++ b/R/phenomena.R
@@ -0,0 +1,35 @@
+# ==============================================================================
+#
+#' Get the counts of sensors for each observed phenomenon.
+#'
+#' @param boxes A \code{sensebox data.frame} of boxes
+#' @return An \code{data.frame} containing the count of sensors observing a
+#'   phenomenon per column.
+#' @export
+osem_phenomena = function (boxes) UseMethod('osem_phenomena')
+
+# ==============================================================================
+#
+#' @describeIn osem_phenomena Get counts of sensors observing each phenomenon
+#'   from a set of senseBoxes.
+#' @export
+#' @seealso \code{\link{osem_boxes}}
+#' @examples
+#' # get the phenomena for a single senseBox
+#' osem_phenomena(osem_box('593bcd656ccf3b0011791f5a'))
+#'
+#' # get the phenomena for a group of senseBoxes
+#' osem_phenomena(
+#'   osem_boxes(grouptag = 'ifgi', exposure = 'outdoor', date = Sys.time())
+#' )
+#'
+#' # get phenomena with at least 10 sensors on opensensemap
+#' phenoms = osem_phenomena(osem_boxes())
+#' colnames(dplyr::select_if(phenoms, function(v) v > 9))
+#'
+osem_phenomena.sensebox = function (boxes) {
+  Reduce(`c`, boxes$phenomena) %>% # get all the row contents in a single vector
+    table() %>%                    # get count for each phenomenon
+    t() %>%                        # transform the table to a df
+    as.data.frame.matrix()
+}