shinyApp(

  ui = fluidPage(
    selectInput("region", "Region:",
                choices = colnames(WorldPhones)),
    plotOutput("phonePlot", height=270)
  ),

  server = function(input, output) {
    output$phonePlot <- renderPlot({
      barplot(WorldPhones[,input$region]*1000,
              ylab = "Number of Telephones", xlab = "Year")
    })
  },

  options = list(height = 345)
)