geolocation API accuracy issues

hey everyone, so i'm running this web tool called 'What is My Location?' which is pretty straightforward: it helps users find their current coordinates and map position. the primary goal, obviously, is to provide super high accuracy for user location data, especially for some of our more niche users who need precise info. but here's the kicker, we're seeing some realy significant discrepancies in location accuracy. this happens a lot, particularly when users deny browser geolocation permissions, or when their network environment, like a vpn or a corporate proxy, really messes with things. the fallback mechanisms we've put in place just aren't giving us the precision we need, and it's frustrating. our current setup is a bit of a hybrid. for the primary method, we're using the browser's navigator.geolocation API. we've got it set with a 10-second timeout and enableHighAccuracy: true, which generally works pretty well when users actually grant permission. but then, if navigator.geolocation is denied or fails for whatever reason, we fall back to a third-party IP geolocation API. we're using one like ip-api.com and we're caching results for repeat visitors within a session to save on calls. we've also been experimenting with a second fallback, doing some server-side reverse dns lookups and trying to pull isp data, but honestly, this is proving even less reliable for really precise user location, it's more like city or region level, not what we need for an accurate IP address lookup. the biggest issue is the jump in accuracy. going from the browser's navigator.geolocation to just IP-based is often hundreds of kilometers off, which, while expected for an IP address lookup, is totally problematic for our use case. also, even with enableHighAccuracy: true, some mobile users are reporting less precise results than we'd expect, especially when they're indoors. and on top of all this, we're trying to minimize api calls to paid services, but the free tiers often have rate limits or just inherently lower accuracy, making it a tough balance. so, i'm really looking for some expert advice here. are there any solid strategies or alternative technical approaches that can genuinely improve location accuracy when browser permissions aren't granted, or when the initial geolocation api is just slow or inaccurate? i mean, are there any client-side tricks we're missing, or maybe some server-side integrations that can bridge this gap more effectively without relying solely on the IP address for precision? any thoughts or experiences would be massively helpful. thanks in advance!