Rob from Twilio here - the firms listed in the first two paragraphs are the new folks who are joining in this round, not the exclusive list of all participants.
BVP did participate in this round - great team to work with.
Have you had an opportunity to check out TaskRouter yet? We released it a few weeks ago - definitely my favorite recent product that works with Twilio Voice:
Mmmm - great feedback. We do provide this service for our phone numbers to do a CNAM lookup on inbound communications - can see how it would be useful for Twilio Lookup as well.
It would be based on the number itself. Obviously with local number portability this is not super accurate, but we do have some customers that find the data useful nevertheless.
Rob from Twilio here - thanks for using the service. Localization and fraud/spam protection are definitely the two most useful for Twilio Lookup, but suspect there are a couple more than might be less obvious.
1) Smarter Routing - quite a few developers have expressed they'd like to know whether or not a phone number is a landline or not before attempting to send a text message. Twilio Lookup will describe whether the number is mobile, landline, or voip so you can choose the appropriate communication to reach the number.
2) Error Checking - While libraries like libphonenumber are useful for determining if a number can possibly exist, there are some conditions where determining if a number does exist is more valuable. This can be used for error checking - if I as a user input a typo in my phone number (e.g. I mistype my personal phone number as '(347) 193-6073' which does not exist instead of '(347) 923-6073')
I also suspect across larger applications carrier info might also contain useful demography. For example, knowing that your users in Montana mostly use Verizon might inform your advertising to surface more CDMA devices in that market.
Ultimately this will probably end up like every other product we release - the killer use case is one we never even considered.
Good feedback - appreciate you sharing. We do have geographic information with each webhook sharing city, state and zip - agree it would be useful to have this in the Lookup resources as well.