I want to develop a web based app which will have a

I want to develop a web based app which will have following functionalities 1. A login 2. After authenticated login, users will be redirected to another web page and there will be a background image. 3. This is the most crucial part, I want users to be able to click on the background image and draw a line on the image which can be saved later. An example of that looks like this

Any ideas which is the best language to implant this kind of functionality?