Add Border and Share
So, this is a little feature that seems to have slipped in without much fanfare into Lightroom for mobile (only iOS from what I can tell at the moment) earlier this year (Lr 8.2.2). If you’ve got a photo that you want to share to social media (or anywhere really) and you don’t want to crop it to a specific aspect ratio for a given platform or you just want a border around the photo, you’ve got an easy way to do it as part of the share/export function.
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First, to find it take the photo you want to add the border to into detail view, and when edits are finished, tap the Share icon to open the Border Options screen.
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From here you might want to start at the bottom and work up by first tapping the desired border size. So, if this was going to Instagram and I wanted to have a canvas that was 5:4 I would tap that icon to start.
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Next, adjust the Thickness slider to your liking. The thicker the border the smaller the photo.
And finally, choose your color. There are a series of preset color swatches you can choose from, or if you want to select a color from the photo, tap the eyedropper icon and move the color picker around the photo to find a color.
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You can go back and tweak settings to dial things in just the way you want them, then tap the Share icon at the top to begin the exporting process.
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From here you can share directly to a social media app or just save the copy to your device and share as you wish. A simple, but useful feature that I hope will appear across all versions of Lightroom in the future.