Getting a GPS fix takes time, so iOS may return a cached location instead of a new one when we call FileMaker's location functions to get a result faster. You can detect when it does this using the "Age" value returned by the LocationValues function; I wrote a blog post in October that describes how to do this. The only solution I've found to guarantee a fresh fix is to keep trying in a loop until the age value indicates a new position.
Thanks Jeremy. Nice article. Sounds like it'll do the trick.