diff --git a/NAMESPACE b/NAMESPACE
index 89b3a1a..cfff8db 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -20,6 +20,7 @@ export(osem_as_sensebox)
 export(osem_box)
 export(osem_boxes)
 export(osem_counts)
+export(osem_endpoint)
 export(osem_measurements)
 export(osem_phenomena)
 export(st_as_sf.osem_measurements)
diff --git a/R/api.R b/R/api.R
index 1726aea..6f112ff 100644
--- a/R/api.R
+++ b/R/api.R
@@ -4,12 +4,19 @@
 #  for CSV responses (get_measurements) the readr package is a hidden dependency
 # ==============================================================================
 
+#' Get the default openSenseMap API endpoint
+#' @export
+#' @return A character string with the HTTP URL of the openSenseMap API
+osem_endpoint = function() {
+  'https://api.opensensemap.org'
+}
+
 get_boxes_ = function (..., endpoint) {
   response = osem_request_(endpoint, path = c('boxes'), ...)
 
   if (length(response) == 0) {
     warning('no boxes found for this query')
-    return(response)
+    return(osem_as_sensebox(as.data.frame(response)))
   }
 
   # parse each list element as sensebox & combine them to a single data.frame
@@ -17,7 +24,8 @@ get_boxes_ = function (..., endpoint) {
   df = dplyr::bind_rows(boxesList)
   df$exposure = df$exposure %>% as.factor()
   df$model    = df$model %>% as.factor()
-  df$grouptag = df$grouptag %>% as.factor()
+  if(!is.null(df$grouptag))
+    df$grouptag = df$grouptag %>% as.factor()
   df
 }
 
diff --git a/R/box.R b/R/box.R
index dcc2b73..3854459 100644
--- a/R/box.R
+++ b/R/box.R
@@ -38,7 +38,7 @@
 #'
 osem_boxes = function (exposure = NA, model = NA, grouptag = NA,
                       date = NA, from = NA, to = NA, phenomenon = NA,
-                      endpoint = 'https://api.opensensemap.org',
+                      endpoint = osem_endpoint(),
                       progress = T) {
 
   # error, if phenomenon, but no time given
@@ -87,7 +87,7 @@ osem_boxes = function (exposure = NA, model = NA, grouptag = NA,
 #' # get a specific box by ID
 #' b = osem_box('57000b8745fd40c8196ad04c')
 #'
-osem_box = function (boxId, endpoint = 'https://api.opensensemap.org') {
+osem_box = function (boxId, endpoint = osem_endpoint()) {
   get_box_(boxId, endpoint = endpoint)
 }
 
diff --git a/R/box_utils.R b/R/box_utils.R
index d5d964f..ab9b483 100644
--- a/R/box_utils.R
+++ b/R/box_utils.R
@@ -33,7 +33,8 @@ plot.sensebox = function (x, ..., mar = c(2,2,1,1)) {
 print.sensebox = function(x, ...) {
   important_columns = c('name', 'exposure', 'lastMeasurement', 'phenomena')
   data = as.data.frame(x)
-  print(data[important_columns], ...)
+  available_columns = important_columns %in% names(data)
+  print(data[available_columns], ...)
 
   invisible(x)
 }
diff --git a/R/counts.R b/R/counts.R
index 6636b1f..854b002 100644
--- a/R/counts.R
+++ b/R/counts.R
@@ -11,6 +11,6 @@
 #'
 #' @export
 #' @seealso \href{https://docs.opensensemap.org/#api-Misc-getStatistics}{openSenseMap API documentation (web)}
-osem_counts = function (endpoint = 'https://api.opensensemap.org') {
+osem_counts = function(endpoint = osem_endpoint()) {
   get_stats_(endpoint)
 }
diff --git a/R/measurement.R b/R/measurement.R
index 48b69e9..fd12197 100644
--- a/R/measurement.R
+++ b/R/measurement.R
@@ -59,7 +59,7 @@ osem_measurements.default = function (x, ...) {
 osem_measurements.bbox = function (x, phenomenon, exposure = NA,
                                    from = NA, to = NA, columns = NA,
                                    ...,
-                                   endpoint = 'https://api.opensensemap.org',
+                                   endpoint = osem_endpoint(),
                                    progress = T) {
   bbox = x
   environment() %>%
@@ -84,7 +84,7 @@ osem_measurements.bbox = function (x, phenomenon, exposure = NA,
 osem_measurements.sensebox = function (x, phenomenon, exposure = NA,
                                        from = NA, to = NA, columns = NA,
                                        ...,
-                                       endpoint = 'https://api.opensensemap.org',
+                                       endpoint = osem_endpoint(),
                                        progress = T) {
   boxes = x
   environment() %>%
diff --git a/README.md b/README.md
index 0cdd517..8a56770 100644
--- a/README.md
+++ b/README.md
@@ -1,9 +1,13 @@
 # opensensmapr
+
+[![CRAN status](http://www.r-pkg.org/badges/version/opensensmapr)](https://cran.r-project.org/package=opensensmapr) [![Travis build status](https://travis-ci.org/noerw/opensensmapR.svg?branch=master)](https://travis-ci.org/noerw/opensensmapR) [![AppVeyor Build Status](https://ci.appveyor.com/api/projects/status/github/noerw/opensensmapR?branch=master&svg=true)](https://ci.appveyor.com/project/noerw/opensensmapR) [![Coverage status](https://codecov.io/gh/noerw/opensensmapR/branch/master/graph/badge.svg)](https://codecov.io/github/noerw/opensensmapR?branch=master)
+
 This R package ingests data (environmental measurements, sensor stations) from
 the API of opensensemap.org for analysis in R.
 The package aims to be compatible with sf and the tidyverse.
 
 ## Installation
+
 Right now, the package is not on CRAN. To install it from GitHub, run:
 
 ```r
@@ -12,6 +16,7 @@ devtools::install_github('noerw/opensensmapr')
 ```
 
 ## Usage
+
 A verbose usage example is shown in the vignette [`osem-intro`](https://noerw.github.com/opensensmapR/inst/doc/osem-intro.html).
 Each functions documentation can be viewed with `?<function-name>`. An overview
 is given in `?opensensmapr`.
@@ -39,17 +44,23 @@ osem_counts()
 Additionally there are some helpers: `summary.sensebox(), plot.sensebox(), st_as_sf.sensebox(), osem_as_sensebox(), [.sensebox(), filter.sensebox(), mutate.sensebox(), ...`.
 
 ## Changelog
-This project adheres to semantic versioning, for changes in recent versions
-please consult [CHANGES.md](CHANGES.md).
+
+This project adheres to semantic versioning, for changes in recent versions please consult [CHANGES.md](CHANGES.md).
 
 ## FAQ
+
 - *Whats up with that package name?* idk, the R people seem to [enjoy][1]
-[dropping][2] [vovels][3] so.. Unfortunately I couldn't fit the naming
-convention to drop an `y` in there.
+[dropping][2] [vovels][3] so.. Unfortunately I couldn't fit the naming convention to drop an `y` in there.
 
 [1]: https://github.com/tidyverse/readr
 [2]: https://github.com/tidyverse/dplyr
 [3]: https://github.com/tidyverse/tidyr
 
+## Development
+
+Please note that this project is released with a [Contributor Code of Conduct](CONDUCT.md).
+By participating in this project you agree to abide by its terms.
+
 ## License
+
 GPL-2.0 - Norwin Roosen
diff --git a/man/osem_box.Rd b/man/osem_box.Rd
index 656d5a9..f891654 100644
--- a/man/osem_box.Rd
+++ b/man/osem_box.Rd
@@ -4,7 +4,7 @@
 \alias{osem_box}
 \title{Get a single senseBox by its ID}
 \usage{
-osem_box(boxId, endpoint = "https://api.opensensemap.org")
+osem_box(boxId, endpoint = osem_endpoint())
 }
 \arguments{
 \item{boxId}{A string containing a senseBox ID}
diff --git a/man/osem_boxes.Rd b/man/osem_boxes.Rd
index 34bb92d..369bb66 100644
--- a/man/osem_boxes.Rd
+++ b/man/osem_boxes.Rd
@@ -5,8 +5,8 @@
 \title{Get a set of senseBoxes from the openSenseMap}
 \usage{
 osem_boxes(exposure = NA, model = NA, grouptag = NA, date = NA,
-  from = NA, to = NA, phenomenon = NA,
-  endpoint = "https://api.opensensemap.org", progress = T)
+  from = NA, to = NA, phenomenon = NA, endpoint = osem_endpoint(),
+  progress = T)
 }
 \arguments{
 \item{exposure}{Only return boxes with the given exposure ('indoor', 'outdoor', 'mobile')}
diff --git a/man/osem_counts.Rd b/man/osem_counts.Rd
index eff45d9..cc7c9ef 100644
--- a/man/osem_counts.Rd
+++ b/man/osem_counts.Rd
@@ -4,7 +4,7 @@
 \alias{osem_counts}
 \title{Get count statistics of the openSenseMap Instance}
 \usage{
-osem_counts(endpoint = "https://api.opensensemap.org")
+osem_counts(endpoint = osem_endpoint())
 }
 \arguments{
 \item{endpoint}{The URL of the openSenseMap API}
diff --git a/man/osem_endpoint.Rd b/man/osem_endpoint.Rd
new file mode 100644
index 0000000..48ac109
--- /dev/null
+++ b/man/osem_endpoint.Rd
@@ -0,0 +1,14 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/api.R
+\name{osem_endpoint}
+\alias{osem_endpoint}
+\title{Get the default openSenseMap API endpoint}
+\usage{
+osem_endpoint()
+}
+\value{
+A character string with the HTTP URL of the openSenseMap API
+}
+\description{
+Get the default openSenseMap API endpoint
+}
diff --git a/man/osem_measurements.Rd b/man/osem_measurements.Rd
index 7ec3b90..d30b809 100644
--- a/man/osem_measurements.Rd
+++ b/man/osem_measurements.Rd
@@ -12,12 +12,11 @@ osem_measurements(x, ...)
 \method{osem_measurements}{default}(x, ...)
 
 \method{osem_measurements}{bbox}(x, phenomenon, exposure = NA, from = NA,
-  to = NA, columns = NA, ..., endpoint = "https://api.opensensemap.org",
-  progress = T)
+  to = NA, columns = NA, ..., endpoint = osem_endpoint(), progress = T)
 
 \method{osem_measurements}{sensebox}(x, phenomenon, exposure = NA,
-  from = NA, to = NA, columns = NA, ...,
-  endpoint = "https://api.opensensemap.org", progress = T)
+  from = NA, to = NA, columns = NA, ..., endpoint = osem_endpoint(),
+  progress = T)
 }
 \arguments{
 \item{x}{Depending on the method, either
diff --git a/tests/testthat/test_boxes.R b/tests/testthat/test_boxes.R
index c1d8892..79b8fd0 100644
--- a/tests/testthat/test_boxes.R
+++ b/tests/testthat/test_boxes.R
@@ -52,10 +52,10 @@ test_that("endpoint can be (mis)configured", {
   expect_error(osem_boxes(endpoint = "http://not.the.opensensemap.org"), "resolve host")
 })
 
-test_that("a response with no matches returns empty sensebox data.frame", {
+test_that("a response with no matches returns empty sensebox data.frame and a warning", {
   check_api()
   
-  boxes <- osem_boxes(grouptag = "does_not_exist")
+  suppressWarnings(boxes <- osem_boxes(grouptag = "does_not_exist"))
   expect_true(is.data.frame(boxes))
   expect_true(any("sensebox" %in% class(boxes)))
 })
diff --git a/tests/testthat/test_counts.R b/tests/testthat/test_counts.R
new file mode 100644
index 0000000..90de81d
--- /dev/null
+++ b/tests/testthat/test_counts.R
@@ -0,0 +1,17 @@
+context("counts")
+
+check_api <- function() {
+  code <- NA
+  try(code <- httr::status_code(httr::GET(osem_endpoint())))
+  if (is.na(code)) skip("API not available")
+}
+
+test_that("counts can be retrieved as a list of numbers", {
+  check_api()
+  
+  counts <- osem_counts()
+  
+  expect_true(is.list(counts))
+  expect_true(is.numeric(unlist(counts)))
+  expect_length(counts, 3)
+})