Dashware can use more or less any format (even imports CSV). AS long as you have the usual GPS coordinates it will interpolate speed distance and so on (you create calculated fields). So a gpx file, kml csv etc should do. If you send me an example file I can try it out. Of course there has to be a time stamp, but if you say its logging every second its a none issue.
For the overlay :
Capture the video from the smartphone(rooted/Jail breaked) add a garbage matte (or whatever your editing program calls it - not all have this effect) and add the actual video from Drone's camera below.