aprs.fi iOS app 1.8 with TNC (RF TX/RX) support

[Heikki Hannikainen]

Hi,

Version 1.8.0 of the iPhone/iPad app got released on 2019-01-21. I forgot
to announce it here, but better late than never.

• Supports attaching to a radio transceiver with a wireless connection to
a BLE TNC. Receives and transmits APRS position beacons without the Internet!

Tested with the Mobilinkd TNC3:
https://store.mobilinkd.com/products/mobilinkd-tnc3

Demo video: https://twitter.com/aprsfi/status/1077358537922306048

Open source (GPL v3) firmware for the TNC3 in case you'd like to improve
it, or make a BLE TNC of your own:
https://github.com/mobilinkd/tnc3-firmware

• Use the filtering feature to select TNC- or Network-sourced data, or a
merged view of both. Other filters do not yet apply for TNC data.
• Dark symbols are more visible on dark map styles now, with a white
shadow
• Some bug fixes for symbol rotation
• Minimum beacon interval slider has a logarithmic scale for better
precision in the low end
• Accessibility improvements (more large text support for those of us with
age vision or other eyesight challenges)
• Requires iOS 9 or newer; iOS 8 support had to be dropped for technical
reasons.

The next version (1.8.1) has the following improvements on top of that,
it'll probably come out in a day or two, pending Apple's review:

• TNC beaconing: Selected APRS packet path is stored in station config,
and defaults to WIDE1-1,WIDE2-1 instead of TRACE2-2
• Beacon view: Improved error reporting for TNC disconnection and network errors
• Beacon view: New switch to enable/disable transmitting altitude
• Beacon view: Improved validation and informational popups about correct AX.25 callsign syntax
• Beaconing has slightly stricter requirement for position fix accuracy (200 meters)
to reduce jumping around a lot when inside without GPS coverage.
• Map: New app setting to enable/disable displaying current location on the map,
sometimes it obstructs the view too much
• Map: Road traffic layer is now disabled by default due to numerous app
crashes in the traffic layer code. Can be re-enabled in app settings.


In case you wonder why some features in your favourite ham apps (in
general) sometimes take a lot of time to happen... to make the iOS app
support BLE TNCs, a total of 110 files needed to be changed, with 5678
lines of code added, 1184 lines deleted.
(https://twitter.com/aprsfi/status/1089216064054013952)

Most of the 1184 deleted code lines were actually modified and replaced by
code in the 5678 added lines; any functionality wasn't actually removed.
The diff is between the previous release in December (1.6.9), and does not
include any of the changes in the included libraries (APRS parser or
such), just my changes.

It's a very crude measure, of course. On Saturday I worked on the app for
some 8 hours, resulting in 403 insertions (+), 207 deletions(-). A chunk
of some 150+ lines got moved around, so some 200+ lines of actual new
stuff. Sometimes you'll find yourself banging your head at some obstacle
for the whole day, and with some luck, at the end of the day, make a
10-line change which fixes the issue. Just to give an idea on the amount
of work needed to make these things happen!

A lot of these changes are needed to support TNCs in general (KISS, AX.25,
APRS parsing, showing and merging data from both TNC and database
backend), so they pave the way for supporting a audio modem, or TCP
network TNCs or such, later on.

- Hessu