TrustExecutor Wow. Osmand is extremely cool, thank you for sharing this! I plan to try this out going forward. I setup an overlay like the article lies out.
Through testing that API that is listed in the article, you can observe the way it works.
Basically, it is just downloading a region image from google earth with a traffic overlay. So if Google is tracking usage of this API and correlating it with ips or something like that, they really arent getting anything besides your general location within several 10s of miles. You could also decrease the max zoom level in osmand, which would decrease accuracy further. Each level of zoom is 2x i believe, with zoom 0 just being the entire earth. the x and y attributes on the api are just coordinates on the projection.
You can also set the update/expire rate for these images in osmand to be whatever value you want, which is nice. However I am curious if there is a style on this api that shows heiristics data. The article is using style 15 which is live traffic data apparently, but I havent found an api description as of yet to see what the others do. Using heuristical data allows for each image to be updated only every once and a while, vs with live traffic data the refresh rate needs to be set low to actually be useful. Although live data is more useful because you can see accidents etc vs heuristical data over a short period would only be really useful for seeing construction etc (that being said, construction is usually what holds me up).
The only real downside to the approach taken here is that it doesnt seem like osmand is smart enough to show you an eta based on data from these traffic images. I suppose I can test that out myself, but right now it is late where I am and there is little traffic to affect the eta either way.
Overall I think this one is the best suggestion so far for privacy. I havent always had the best luck with OSM based mapping apps but osmand is by far the most powerful one i have seen so it could be better. Either way it can always just be used for traffic data too and then I could plan a general route and continue using my basic nav using my offline gmaps. Really, an app that can show me traffic AND navigate well would be a complete luxury to me haha, so I am not in need of that. One or the other is fine.
Thanks everyone for their suggestions so far!