diff --git a/presentation/ApplicationCategories.R b/presentation/ApplicationCategories.R
new file mode 100644
index 0000000..4834f0b
--- /dev/null
+++ b/presentation/ApplicationCategories.R
@@ -0,0 +1,33 @@
+library(conflicted)
+library(yaml)
+library(RPostgreSQL)
+library(tidyverse)
+conflicts_prefer(dplyr::filter, 
+                 dplyr::lag)
+library(magrittr)
+
+# read the password from file
+credentials <- yaml.load_file("../rapids/credentials.yaml")
+pw <- credentials$PSQL_STRAW$password
+
+#load the PostgreSQL driver
+drv <- RPostgres::Postgres()
+
+# creates a connection to the postgres database
+# note that "con" will be used later in each connection to the database
+con <- RPostgres::dbConnect(drv, dbname = "staw",
+                            host = "eol.ijs.si", port = 5432,
+                            user = "staw_db", password = pw)
+
+rm(pw, credentials) # removes the password
+
+# check for the bluetooth table, an example
+dbExistsTable(con, "app_categories")
+
+df_app_categories <- tbl(con, "app_categories") %>% 
+  collect()
+
+head(df_app_categories)
+table(df_app_categories$play_store_genre)
+
+dbDisconnect(con)