We found a lot of app contain http/ftp(the ftp protocol is not discuss today) server to upload file/video/music(like GPlayer). that's let me interest how to implement it on a app. according to my survey, if you want to do it on Android. you can use NanoHttp(implement by java.net.ServerSocket). on the iOS, you can use CocoaHTTPServer(implement by sys/socket). Btw those lib is not make sure fully support HTTP spec.
picture: the screenshot of upload page of GPlayer (support drop-n-upload feature!)