I’m curious about how common this setup really is among SOTA activators.
How many of you are able to use APRS directly from your mobile phone while portable, either on conventional VHF APRS or LoRa APRS?
For example, using APRSdroid or a similar application together with a radio/TNC, particularly through a Bluetooth KISS TNC.
I’m especially interested in roughly separating these cases:
You know what APRS is, but don’t normally use it.
You use APRS occasionally, perhaps only for position/beaconing.
You can send and receive APRS messages from your handheld.
You have actually used a Bluetooth KISS TNC + phone setup in the field.
You use LoRa APRS from a phone or portable device.
My suspicion is that the last two groups are very small, but I’d like to find out rather than assume.
The reason I’m asking is that I’m currently developing an application which uses APRS as one of its transports for centralised store-and-forward messaging, with the idea of giving APRS a practical communications role when cellular Internet is unavailable.
This isn’t intended as a presentation of the project — at this stage I’m mainly trying to understand how much familiarity there already is with APRS messaging and, especially, Bluetooth KISS TNC operation among potential users.
It would also be useful to know what equipment/software you use if you already have this capability.
For instance, in my case, the VHF APRS network on 144.800 MHz and the LoRa APRS network on 433 MHz in my region both have a decent number of iGates, so they provide a useful way to send and receive messages when cellular Internet is unavailable.
I currently use this for sending SOTA spots and also for sending WhatsApp messages through the APRS WSAPP service.
My setup is simply an Android phone running APRSdroid, with either of two Bluetooth KISS TNC options: a LoRa TNC, or a VHF setup using the VR-N76 handheld.
Like many here, I use one of these (which matches the last case in your list). Once it is configured with frequency and callsign, it works standalone for position/beaconing. With changes to the firmware, it can be controlled by a mobile phone (similar to this) to go beyond the position/beaconing case, but I am not aware of any significant developments in that direction.
Thanks for the reply. In your case, the device can operate as a Bluetooth KISS TNC and it could be used for much more than beaconing. A phone could use it as its APRS Bluetooth interface and exchange messages phone to phone with another user who is connected eihter via regular Internet or through APRS (VHF or LoRa).
That is really the direction I’m exploring: using existing APRS infrastructure not only for position reporting, but as a practical store-and-forward communication between phones.
I have a LoRa tracker (T-beam) and connect to it via Bluetooth to send spots using APRSDroid. I have used it in the past for 2 way messaging, although it is quite slow.
I also have an FT3D and have used it for beaconing and sending spots on 2m, but the interface is tedious to use compared to a phone so I don’t use it as much.
Thanks Pete. I’m currently working on an open-source server and app around this idea.
My main motivation is very simple. I want to be able to communicate with my wife when I go somewhere off-grid, and also with friends when I’m on a two or three-day trek and there is no cellular coverage.
The idea is that they could just have the app installed, much like WhatsApp or Telegram, while I could reach the service through VHF APRS or LoRa APRS when Internet is unavailable. Winlink is another transport I’d like to add in the future.
I’ve always felt a little uncomfortable going into the mountains and becoming totally unreachable. It seems to me that the existing APRS infrastructure could be put to very good use for this kind of messaging.
I bought a Yaesu H/T specifically for this purpose when I first started doing SOTA. The U/I is TERRIBLE, but it gets the job done. I don’t use it all that often - it is amazing how many summits have usable cell service these days.
My preferred method of spotting when I don’t have cell service is SOTAMat:
On my KX2 with a SOTACat connected, this is a very easy way to spot. WAY easier than suffering the Yaesu U/I.
My main use case for APRS on summits with no cell service is finding other stations for S2S (the ‘/spots’ command).
I have thought about getting something like a Mobilinkd and using my phone, but that is just another thing to carry / remember to charge. Why Yaesu can’t come up with an H/T that has a phone app to interact with APRS over BT is beyond me! I guess that technology is too advanced for them in 2026
In what kind of conditions you would have access to aprs repeater but not cellphone service ?
From my experience, if you are in a closed valley, you have no reception , no VHF line of sight. If you are on a summit with long view range , you have cellphone and VHF.
If I need to send a message from the bottom of a remote valley, I use my Garmin inreach. Eventually I could use sotamat on HF, where I pre recorded a few messages for my wife.
I do not use aprs and do not really get the point of it.
I use the SOTA APRS device as well as a phone. In G/NP I don’t get much coverage and the phone fills in some of the gaps.
My only use case is if a chaser wants to guess how close I am from a summit. The coverage isn’t good enough for anything that relies on it. It is interesting and I have a gateway at home too.
There used to be quite a few summits here in W7W that had good APRS coverage but zero cell service (at least via my cell provider). I think the main issue is that the cell towers use ‘beam forming’ and when you are on a summit they don’t see you because you are above the normal coverage area. Often if I put my phone in to ‘airplane mode’ and then back to normal mode, it will get the cell tower’s attention and I will get service for a short while.
Posets summit for instance, and many many summits in EA. C3 (Andorra) is also an example.
In the summits, you have no cellphone service but almost always have APRS access. Not from the valleys, but if you are on an elevated position it is very probable that you reach a digipeater or igate from France or Spain.
I don’t have Garmin inreach and I have no idea how it works, I will look into that. But I think that the APRS network is quite unique and I’m starting to love it (and hate it, equal parts hi hi).
Ok, it never happened to me. 100% coverage on my activations so far.
The problems rarely happen on the summits, always in deep valleys or cliffy terrains
It’s a satellite emergency communicator. You press a button and they send the helicopter. It also does 2 ways text messages and GPS tracker. It’s a very excellent device but… It’s a subscription €€.
Sotamat however is free and very powerful but you need to put up your HF antenna… And when you are injured for example… not easy I imagine.
Yeah, in our region it is very common to lose service when you reach the summit, specially if you turn on the radio, find a free frequency and try to send a spot
I know sotamat and it is very useful, but having to prepare the messages in advance is a bit of a limitation for the kind of use I have in mind.
What I’m trying to achieve is real-time, two-way communication over APRS. Something closer to using WhatsApp or Telegram, where you can have an actual back-and-forth conversation. So far, it’s working quite nicely.
I’m calling it OpenQSP (QSP meaning to relay a message to another station) and all the code is available on github.
I know many of the APRS services, but I feel we could go a step further. Yes, I can send a WhatsApp message or an SMS, but can I have a fluid, real two-way conversation over APRS?
APRS already makes that possible, with some limitations, of course. What interests me is that the network is huge, already deployed, and in my opinion still very underused for this kind of communication.
I also wonder! They have bluetooth, but only for their headsets… not for APRS… I bought a chinese radio and it works like a charm for APRS over bluetooth.
It’s very cool and I agree that sending real time text messages would be great. However, did you try it on the French side ? because when I see the map of the aprs repeaters … It’s quite sparse to say the least
Not me I save my phone for the SW3 page if I can get the internet on the summit.
I spam out a group txt msg to a few regular chasers, and do my own Spots from the summit on my phone. Have tried my FT5D on VHF APRS but can’t reliably access any Digi’s or locals on that mode its a waist of RF and Battery in my area.
Yes, but not away from the Pyrenees. When I go to France I usually have very good APRS service, even too many stations heard at the same time and no time to transmit.
What I can tell is that there are a ton of LoRa iGates and digipeaters in France, as far as I can see:
I don’t know how to filter out Lora devices in aprs.fi…
But the good news is that you could try to find a cheap LoRa APRS (like a Lilygo or Heltec) and see if the network works well. But if you don’t have problems with regular internet you won’t probably use it much (maybe for beaconing)
I’ve tested APRS for spotting and gotten it to work with my phone, APRSdroid, and just holding the PTT down on my HT when I hit send message. Never actually used it in the field. I either have data coverage, SMS coverage, or I rely on alerts and RBNhole for spotting.
