Google has just released a new update for its YouTube app for Android devices with a capability to trim videos before uploading to YouTube. users can select a desired video from theor devices using the YouTube app and it will show you the new trimming interface and can simply tap and swipe the scroll switch to choose an exact frame. With the new scroll switches you can now select the precise frames as start and end of the video. also , users can watch the video preview of their desired trimmed video before uploading it.