I found this while researching Mobi:
What I found is that the reception in my local neighbourhood was possibly average, but real world measurements by myself (albeit for less than one week) indicate reception in my area (15 to 20 ASU) far exceeds the network average (5 to 15 ASU) in other parts of the GTA where I have tested my phone.
However, I'm curious about how old data is handled with these sites. As new towers are added to a network, how would old data get scrubbed from the database? Would it get overwritten, averaged, removed after an expiry date, or some other algorithm? If it is not handled properly, the database could become contaminated with stale data.