Using ND Filters is a great way to pro-long your exposure or capture a normal exposure throughout your entire shot when it wouldn't have been otherwise. Up until now, you've had to have a piece of glass in front of your lens that would darken areas of your shot, but Sony just changed everything by releasing the Sky HDR App.
Sony's Sky HDR App allows you to use three different presets: Blue Sky, Sunset, and Graduated ND. With the filter preset selected, you are able to select what part of the image you want effected by the filter even if it's on an angle. If a properly exposed sky is making the scene around it too dark, you can now filter the sky so the scene is all perfectly lit. Take a look at the examples below to see why this is a must have app.
Compatible cameras: NEX-5R, NEX-6, NEX-5T, ILCE-7, ILCE-7R, ILCE-6000, DSC-RX100M3, ILCE-7S, ILCE-5100, ILCE-7M2, DSC-RX100M4, DSC-RX10M2, ILCE-7RM2, ILCE-7SM2, DSC-RX1RM2.