Reactive time example

server.R

shinyServer(function(input, output) {
  output$currentTime <- reactiveText(function() {
    # Forces invalidation in 1000 milliseconds
    invalidateLater(1000)
    
    as.character(Sys.time())
  })
  
  randomData <- reactive(function() {
    if (!input$pause)
      invalidateLater(750)
    runif(4)
  })
  
  output$random <- reactiveTable(function() {
    matrix(randomData(), 2, 2)
  })
})

ui.R

shinyUI(bootstrapPage(
  div(class="container",
      p(strong("The time is:"),
        textOutput("currentTime")
      ),
      p(strong("Here's some random data:"),
        tableOutput("random"),
        checkboxInput("pause", "Pause updates", FALSE))
  )
))

> server <- shinyServer(function(input, output, session) {
+     output$currentTime <- renderText({
+         # Forces invalidation in 1000 milliseconds
+         invalidateLater(1000)
+         
+         as.character(Sys.time())
+     })
+     
+     randomData <- reactive({
+         if (!input$pause)
+             invalidateLater(750)
+         runif(4)
+     })
+     
+     output$random <- renderTable({
+         matrix(randomData(), 2, 2)
+     })
+ })
> ui <- shinyUI(bootstrapPage(
+     div(class="container",
+         p(strong("The time is:"),
+           textOutput("currentTime")
+         ),
+         p(strong("Here's some random data:"),
+           tableOutput("random"),
+           checkboxInput("pause", "Pause updates", FALSE))
+     )
+ ))
> shinyApp(ui, server)

Its cool... ^_^
https://beta.rstudioconnect.com/content/3073/