Twitter currently pays vanity short code fees and
SMS fees for mobile-terminated and mobile-originated messages in the United States and Canada. Twitter accepts mobile-originated messages to a long number in England. An intermediary such as
Sybase 365 sits in between Twitter servers and the cellular networks of
AT&T,
T-Mobile,
Sprint,
Verizon,
Bell Canada,
Rogers, and more. A subset of Twitter users take advantage of
SMS update notifications but this feature is currently
a drain on Twitter cash reserves.