from:
http://wiki.maemo.org/Documentation/...cation_methods

It is not entirely clear to me, if positions retrieved via ordinary or assisted fixes are cached somewhere.

What i would like to know if it's possible that if i ever get a fix using assisted method, and i want to start at or near the same position at some time later, can i re-use a once retrieved position also in applications if assisted method is switched off?

So, to rely on un-assisted methods but re-use location cache?


This would help tremenuously when i'm abroad and don't want to go online (or can't), and also don't have free sky and endless time to wait for unassisted fix.

// Sygic, Marble, modrana etc.

@don_falcone,

My understanding when reading that is that the cache is only updated when using ACWP, i.e. the mapping of cell-id to a position by an external server (not by GPS).

So, if you later use CWP (SIM cell-id, no GPS, no network) and the cell-id is in the cache, you should get the position (as fetched by ACWP) without needing a (data) network connection or GPS (but obviously being registered with GSM, so that there's a cell id).

But that's just my reading of it. If you have time, give it a try, and for extra bonus: find out where that cache is kept!

Essentially, what you describe is how handheld gps operates. Indeed it should be the default for all gps IMO. However, last position is useful when combined with an updated almanac. Handheld gps stores that but I think the n900 and most other phones don't. The going online bit likely provides that functionality. Otherwise the phone does a tedious blind sky search.
My point is: the almanac.

...i remember the iOS and Android location caching ("tracking") issues that stirred up quite a bit of trouble. But that'almost s exactly what i need...

EDIT: I still have my external, tried & tested BT Royaltek GPS mouse that i wouldn't mind at all using again in the car. After all, when i still used the N73 as my main phone there was no other choice. But that one tests that i did using Sygic on the N900 wasn't successful; a fix was not retrieved over BT IIRC.

Also, i'm not sure the N900 can maintain more than one simultaneous BT connection. (Currently, it's always connected to my carkit.)