leaftlet

library(leaflet)
library(dplyr)

my_map <- leaflet() %>% addTiles() %>% addMarkers(lat = 31.2228559, lng = 121.4729522, popup = "where I am")
my_map

set.seed(123)
df <- data.frame(lat=runif(20,min=39.2,max=39.3), lng=runif(20,min=-76.6, max=-76.5))
df %>% leaflet() %>% addTiles() %>% addMarkers()