如何在rails app和carrierwave uploader中从移动设备上传图片

We have a web application in ruby on rails. Now we are developing API and an app for android and iphone. We are using titanium for mobile app. In the web application to upload file we use carrier wave. I am following same process as shown in railscast to upload files using carrierwave. My question is how can I do this in mobile app. I need idea and sample code if possible. Following is my code that works okay for the web version of the application.We have a web application in ruby on rails. Now