Website that allow user to upload picture with their smartphone
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I believe a lot of people will enjoy this interesting post including myself of course.
I would like to know a way to tackle this problem:
Imagine user viewing a web app inside their smart phone, when user clicks the upload button, they are allow to instantly go to their gallery and click whatever picture they want for upload.  
So, is there a way to allow them to upload image from their phone into the web app??(More on the communication level) 

(At first I wanted to ask for a more direct way of getting the image by accessing user's smartphone camera, but I know it will be extremely difficult to do so from a website stand point, usually this requires a native app for it to be done which I am not planning to make one anytime soon.) 

Anyways, to further explain my question:

    _________________                                           _______________
    |_______________|                                           |_____________|
    |   web app     |-------> Communication to get??----------->| smartphone  |  
    |               |<----- --return the image(bytes)-----------|  (gallery)  |
    |               |                                           |             |
    -----------------                                            -------------

I am more concern with the communication layer and the concept more than the actual coding itself. Thanks in advance. (I strongly believe that this will be an interest one here.)



