Just been looking at the UKC News article about OS Locate.
http://www.ukhillwalking.com/news/item/70813/mrt_in_smartphone_appeal_to_wa...
That makes me think about the wider matter of smartphone grid reference apps. It has been covered on here before
http://www.ukclimbing.com/forums/t.php?t=633064
but this is an ever-moving target as apps are written and developed.
OS LOCATE
In many respects, OS Locate is a wonderful app. It will get you a grid reference so long as you have visible sky and GPS enabled.
There is a wee problem with OS Locate that appears on a few phones. On some phones of a smaller format or certain types of display there isn't enough room for all the fancy stuff so the grid reference, the thing you really need to save your life, is sacrificed for all the logos and the dodgy compass. Reducing the font size in the phone setting may help. Ordnance Survey don't seem bothered that the app developer is happy to sacrifice the grid reference in favour of a few fancy logos.
The grid reference is the thing that works well in OS Locate. The compass and altitude are not likely to be as reliable. If you intend to use the compass facility then make sure you understand the calibration routine.
VIEWRANGER
This is a very good mapping app that you then have to buy maps for. It is very useful and reliable app that operates without needing phone coverage and displays the grid reference above the map display.
SARLOC
This was written by a guy called Russ Hore and is used by mountain rescue teams across the UK and in a few other territories. It requires phone data coverage to work.
As an ordinary mountaineer, all you need to know about SARLOC is that it exists and you need to be able to open a text message from a rescue team and use the hyperlink in the message to open the phone's browser. Once that is done, your position is automatically sent to the rescue team.
Some smartphone browsers struggle with the 2G coverage in many mountain areas. Opera Mini works with 2G GPRS and EDGE signals better than most other phone browsers. There may be other browser options out there that will do the same.
WHAT'S YOUR EXPERIENCE?
So what have you used?
How does OS Locate work for you?
Are there other similar apps?
What's the latest?
What works only with phone coverage and what works without?
Have you been rescued by Russ's SARLOC: how was it for you?