I normally always consult the forums that I've been asked to consult before asking any questions. I haven't seem to have found an answer for exactly what I am looking for, thus I am posting this.
Basically, I would like to know if it would be possible for developers to build apps for use within the Yahoo Mail Service itself. Like how you see apps like "Attachments" or "Calender", I would like to know if it would be possible for third parties to build useful apps for use within the mail service itself. It will obviously be mail-related, but considering how vital email has become, I'm sure there are plenty of useful apps that could be created for use within the mail service itself.
I understand the risks involved with allowing third-parties to build such apps, but considering that these apps should run on Yahoo's own servers, etc. I'm sure the issue of security can be overcome quite easily.