Manually retrieve video from an in-app recording. (5th Gen iPod)
If the App support this feature You can copy the video from iTunes else you have to use third party applications like PhoneView or iFunBox

Using iTunes:


Open the iTunes
Connect the device
select the device from sidebar or device menu
Select the Apps tab on device window (right side column)
Scroll down, below the apps list there will be another list of app
Search for the your app in that list (if the app support shared folder it will be listed here) and select.
On right side the shared document for that app will be listed from there You can select and save the video.


Using Other App (PhoneView or iFunbox)


Download and install the app from the links above 
Connect the device and open the utility (PhoneView or iFunbox)
Select The device from the left side bar
Double click to list the user application
Search for your screen recorder app and double click on it to show the content
Inside the app there will be a document folder.
There you can see your video. just drag the file to desktop or you can export the file to some other location from the menu.