I put together an online webpage with 3 graphical fuel giages for the 3 silo's we have at work, somewhere on this site theres a screenshot, the esp acted independantly as a webpage and uploaded the page which was written in javascript,html,css.
All is stored via spiffs in the esp's memory, the guages are updated using ajax.
At first I tried to do it all with an esp and a arduino using At commands to the esp module, but just couldnt get it to work, then I used the arduino ide and prgrammed the esp directly and got the thing to work well with just the esp, no arduino.
Beware the esp8266 01 behaves weirdly when signal level is low, they might have sussed that in firmware now, still a good idea to use the signal level meter in the esp though and detect low signal, also good if you have a project permanently online periodically check the connection and reconnect if its lost.