I am searching for a mailing list webapp (think MailChimp) which is able to segment message recipients based on worldwide location, be that by post/ZIP code, town/city, country or less desirably (unless has a good API) on Latitude and Longitude.
I have been in contact with the aforementioned MailChimp, plus a few other hopefuls with no avail - MailChimp, although able to segment based on ZIP codes, only currently supports this for US addresses and I require worldwide.
Any suggestions for commercial (paid for but reasonable) or open-source (free) greatly appreciated.
Update: Another service, activecampaign.com allows segmentation on location, however, only by where the user opens email. Another requirement is that I need to be able to segment on a given location (e.g. given by recipient at sign up).