When you take pictures with your smartphone or your tablet do you hold the device horizontally or vertically? It makes a difference, depending on where you plan to use/show the image.
My advice: take the picture holding the device horizontally — unless you plan to place the image in a vertical frame. See how much more picture shows on a wide screen? (We are so used to holding our phones vertically to talk on them that we naturally use them in that position for other programs. It might take some time to remember to turn it “sideways” to take a picture.)
Of all of the options for what to do with the pictures and videos you take — and there are many — most of them are better served by a horizontal image than a vertical one. Your computer and TV screens are wider than they are tall. The electronic picture frame your kids gave you is horizontal. Digital cameras are oriented horizontally. Most do-it-yourself picture book themes are oriented horizontally. A horizontal image will fill the space completely.
Vertical pictures will work in these applications; but not as well. If the image is vertical and the screen is horizontal, you have to choose to 1) crop the top and bottom of the image to create a full-screen horizontal picture, or 2) see the full image smaller and with black spaces filling in the area to either side).
Please don’t miss an opportunity to capture a great moment — snap it any way you can! — but if you have the time to consider the shot, turn your camera horizontally. You might be glad you did.