I'm wondering if there is a way to use the CREST or API to fetch real-time data about the location of a given player after authenticating with a web-service through the normal web browser instead of using IGB features?

What I've found is this article;
http://wiki.eve-id.net/APIv2_Corp_MemberTracking_XML

But it says the cache mechanism is "Modified short Cache", which basically means this information might be outdated at the time of fetching if I understand it correctly.

Lets compare to Siggy that use the IGB; This requires all players to have their IGB open in order to see their location which is a problem and wormhole chains don't map. What I want to do is not unlike Siggy but except for mapping wormholes I want to build an interface for corps in order to get real-time location of their members.

Would this be at all possible without using the IGB? I'm thinking the polling interval would be somewhere between 5-15 seconds for this to work.

Please tell me this is for corp members only, right? Because otherwise this data would be very heavily abused. I mean, think about it, you could set up a system that automatically polled every character online, so you could see real time about where fleets were, what systems to avoid, where nobody had gone in hours and would have lots of anomalies and sites and stuff, etc.

Would that mean that we have to use firefox or chrome all the time then?

I'm really hyped about the new CREST update as described in the developer blog! Good job and thank you!

I have one follow-up question; What application permission is needed for the CharacterLocation call (is it publicData?), and what would be the API access mask?

Yet again, awesome work! I'm really hyped about getting started with my application.