As it turns out, generating lightning between two endpoints can be a deceptively simple thing to generate.  It can be generated as an L-System (with some randomization per generation).  Some simple pseudo-code follows:

segmentList.Add(new Segment(startPoint, endPoint));

offsetAmount = maximumOffset; // the maximum amount to offset a lightning vertex.

for each generation (some number of generations)

for each segment that was in segmentList when this generation started

segmentList.Remove(segment); // This segment is no longer necessary.

midPoint = Average(startpoint, endPoint);

// Offset the midpoint by a random amount along the normal.

midPoint += Perpendicular(Normalize(endPoint-startPoint))*RandomFloat(-offsetAmount,offsetAmount);

// Create two new segments that span from the start point to the end point,

// but with the new (randomly-offset) midpoint.

segmentList.Add(new Segment(startPoint, midPoint));

segmentList.Add(new Segment(midPoint, endPoint));

end for

offsetAmount /= 2; // Each subsequent generation offsets at max half as much as the generation before.

end for

Essentially, on each generation, subdivide each line segment into two, and offset the new point a little bit.  Each generation has half of the offset that the previous had.

This  shows how to communicate with Parse.com, a back-end data service, from a Corona SDK app. You should be able to adapt it to your needs with minimal changes. See main.lua for a barebones UI.

To use the parse.lua module, add:

Parse = require(“parse”)

to your main project file and refer to functions as shown in main.lua.