If you are into ggplot2, it is now super-easy to add interactivity to your graph. Just take your static ggplot object pl like the following
That's it. You can configure your tooltip text with ggplotly(pl, tooltip = "text"), see my Rmarkdown example. And it works not only for a simple scatterplot but for more complex graphs as well, as @cpsievert tweeted today.
There are now also many easy-to-use htmlwidgets. And with the ggiraph package, you get now your click as Shiny input.