I’ve been using Adobe Figma CC to design gallery walls lately; figured it could be cute to share that process cause it’s pretty straightforward and super useful :) 
I have like a billion 1-3" gallery black framed prints of all sorts of sizes, and not a lot of floor-space to try a bunch of configurations out, so we gotta get digital. I start by getting individual pictures of each frame 
then I can bring each shot into photoshop and perspective warp to automatically fix lens distortion and my shakey hands lol
each image can go in figma and be resized now. I measure the IRL frame in cm, and set each rectangle in figma to that size * 10px to keep things consistent. (e.g. this frame is 52cm x 67cm) 
with all the frames in there, I can rearrange to my heart’s desire, even deciding the real life spacing between frames. today i’m hanging a wall around my tv. 