Recently, I got a complaint letter from a user of our weather category app 
RadarNow! regarding our new NWS Alert feature. This feature sends out NWS 
Alerts based on the user's location. RadarNow! notifies the backend its 
location and the backend reverse geocodes that location into a state and 
county. NWS Alerts are issued by the county.

The user's complaint was that he and his wife, both with identical phones, 
were receiving different alerts. In theory, they should be receiving the 
same as they are in the same location and again, in theory, the same county.

After some investigation, the issue turned out to be due to the accuracy of 
the Network Location feature in Android. Both users had accuracies of over 
2,500 meters. Normally this wouldn't be a problem but they also lived in a 
border area and one that's rural. Rural areas have more errors in location 
that highly populated ones. 

The fixes must have been based on different cell towers and because they're 
right on the border of Nevada and Arizona, that calculated out to one user 
being in Arizona and the other in Nevada. Naturally, that meant to 
RadarNow!'s backend that they were in different counties so different sets 
of alerts were sent to each of them.

Is this a feature or a bug?

There's always a trade off between accuracy and latency in regard to 
location fixes. For the radar display, 2500 meters is acceptable  For most 
users, that would be the case as well. For these people, it wasn't. So in a 
way, it's a bug in that it allowed the backend to calculate them 
incorrectly into different counties.

On the other hand, it's a feature in that we take the fastest possible fix 
and avoid GPS to improve response time and decrease battery usage. GPS is 
only used when Network location isn't available.

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