Brilliant Alistair, many thanks.
It seems churlish to suggest improvements, but you did ask:
Some way of relating time/height with position on the map ?

On Thursday, 20 August 2015 22:45:10 UTC+1, Alistair Green wrote:
Dear Pilots,

Recently I started using XCSoar on my smartphone to record IGC logger
traces of my flights in club gliders. Naturally I wanted to review my
flights on a PC afterwards, but this was not easy to do without expensive
commercial software. Some free programs exist, but I found them to be
tricky to set up and awkward to use on a small laptop screen.

So, I decided to write my own IGC viewing software, and release it for
free.

The result is now online at:

https://alistairmgreen.github.io/jsigc/

and the full source code is available from:

https://github.com/alistairmgreen/jsigc

It is written in JavaScript and runs inside a web browser, which means that
no installation is required - simply go to the web site, click the button
and select a file. (Note that all of the processing happens on your
computer; nothing is ever uploaded to the Internet.)

The layout of the web page adjusts itself to match the screen size. I have
used it on a large desktop monitor, a 15" laptop, a small netbook and a
smartphone.

At present, the software has the following features:

* Interactive map showing the glider's flight path and the declared task
(if any). The map data comes from the OpenStreetMap project.

* Graph showing the GPS height and pressure altitude as a function of time,
either in metres or in feet.

* Display of any "header" information included in the file (pilot name,
glider registration etc.)

Of course it is by no means a replacement for "SeeYou" or similar, but I
hope that it will be useful to somebody.

I intend to make further improvements in the future, and would be grateful
for any input from the community. Comments, suggestions and bug reports can
be left on the GitHub issue tracker:

https://github.com/alistairmgreen/jsigc/issues

Anyone with programming or web design skills is more than welcome to make
their own copy of the code and add some new features or cosmetic tweaks. I
would love to receive a GitHub "pull request" with your enhancements.

Thanks for reading.

Regards,

Alistair Green
Bath, Wilts & North Dorset Gliding Club, UK

P.S. In case you have never heard of "GitHub", it is one of the biggest
computer programming sites on the Web. It provides tools for sharing
program source code and merging together changes made by different people,
allowing programmers all over the world to collaborate.