If you want to reduce file size and/or capture a long video you may need to reduce the quality of your video recorder. This can usually be accomplished while you are in your mobile device's video recorder mode. Look for options and then select a lower quality resolution and if there is the option choose 3GP as the video format. This will reduce the file size so that it is quicker to email your video. This is especially useful for devices that have a limitation on attachment size.