GPS data from 2 phones to one raspi

Just getting started with Blynk (great concept & execution) . Already have Blynk garage door opener implemented with Huzzah to replace lost remote

For next project I am trying to develop a Blynk app that allows me to determine the distance and bearing between two phones. Each phone sends it’s GPS coordinates to a raspi which then does the spherical geometry calcs and posts back to a Blynk LCD on each phone the distance and relative bearing (same display on each phone). [this is for setting up a sailboat race course with volunteers of varying experience]

My current strategy has a separate Blynk acct on each phone with two js programs running on raspi (each program with a single auth code ) and sharing data via disk writes. Not very efficient. and somewhat problematic. and does not expand well for multiple users.

Is there a simple way to share common project between phones and differentiate where the GPS data are coming from on raspi?

appreciate any help


Yeah, I don’t see a simple way, because inside single project you can’t distinguish which phone sent what.

IMO, a good solution requires a simple web server which would get data from different projects and return the calculation result. A free server on heroku or alike would cover the needs. And expanding is feasible.

The Webhook widgets could be used for easy app-server communication setup.

2x blynk projects
2x esp’s
Bridge mode to connect them

Each ESP has its own Auth code… one for each device.

Then you pick one ESP to be the master and one a slave.

then you set up the master ESP to just report the GPS info as you would normally.

then set up the second ESP to just send its own GPS data via Bridge to a virtual port on the master.

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when app is closed and user is signed out The GPS Trigger widget or any one will be working?

Sorry can you please rephrase the question?

Actually you can instantiate several blynk clients inside one Node.js script. That’s it.

can you explain more?


Not really a rephrase…

However, the answer to your question is yes. The app is just a “dumb” app… it can be closed, logged out, unused, and the HARDWARE and SERVER will continue to talk to each other and exchange data.

ok i understand you but i mean The GPS Trigger that work with APP and Phone.