yes, that is basically what soru meant, to easily link the phone to the 3ds and then just forget about the app. Not translation layers or something. Such a companion app could also sync steps or other things over to the 3ds, dunnoThis is neat, but I think the "easiest", read most user friendly, option would be to separate things out between phone and 3DS app + Luma3DS patch for background transfers, and all the communication is handled over internet via centralized server.
Basically the main app is on the 3DS, it should allow you to create a simple profile on the central server that holds all the relevant street pass information. Either via a manually created profile, or an automatically created one based on whatever unique information is on the 3DS. Other functions would only need to be something like a one button upload of new street pass data and manual download for convenience. This app could also keep track of all street pass data, and whether it came from the 3DS itself or was downloaded from the server instead.
The Luma3DS patch, if possible, would basically just upload and download new things through the app in the background, either on boot, once per hour, or something like that.
Meanwhile the phone app would basically just be the companion app, download it, scan a custom QR code on the 3DS to sync it to the same profile on the server, and then listen for other people running the same app. If there's a hit either phone transmits that hit to the server, the server "exchanges" the data internally, and both people can then download the new street pass data the next time they boot their 3DS near a wifi location.
While this approach would still be incredibly complex, it should skip a bunch of stupid translation, conversion, and privacy issues since most of the sensitive bits are entirely contained within the central server. It would also make it fairly easy to set up an account as most of that could be automated, especially on the phone.
It should also help deal with security concerns over bluetooth, as basically nothing but a short ID would need to be transmitted, which should be simple to sanitize so it can't be used to run arbitrary code on either phone. Similar for the server handling everything, the only streetpass data would come from 3DS systems, the phones would only ever upload an ID, a time stamp, and probably not much else.
Edit: Maybe this is something the pretendo devs could help with, too. If you could piggy back off of their auth system and infrastructure that might streamline a thing or two.
1. is there a good read somewhere how to make luma sysmodules / patches?I'm not sure anyone's made any kind of Luma patch yet capable of doing things like that in the background. Seems like the sort of thing that could cause heaps of problems. On the other hand, maybe it would be possible to somehow patch the existing 3DS background services? In any case it would probably be a whole lot easier just to run the thing manually.
This is one of those cases where I think if it was feasible to make an app like that, someone would have done it by now. The closest thing I can think of is the Canadian COVID contact-tracing app, which I understand ultimately failed because not nearly enough people bothered to install it.
2. yes, when soru formulated the initial post she also had the covid tracking api stuffs in mind
yeah, as stated, it is currently only an early tech demo, things will get better eventuallyWorks nicely, and I'm sure will be better if/when more people adopt it.
It could use a little more verbosity - I initially thought it had crashed as there was a long period of just black screens before the "succesful upload" message and again before the download message.