Currently, standard and service interconnection of MMS is being completed. Hardware ability of MMS terminal varies. There are many kinds of MMS message format which can not be browsed each other.

目前多媒体消息服务(MMS)的标准和业务互通尚待完善，MMS终端硬件能力不统一，MMS消息格式种类繁多难以互相浏览。

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This has helped make it a popular alternative to SMS and MMS message services.

BBC: Whatsapp

It can send a message to all message addresses (phone number, e-mail address, instant messaging screen name) for all message types (voicemail, e-mail, instant message, SMS, MMS, fax).

FORBES: Magazine Article

The Stop Texting Fair Use Act, or STFU Act, would apply to message transmitted using the Short Message Service (SMS) as well as messages containing image, video, and sound content (MMS messages).

FORBES: As Deficit Soars, Congress Suggests New Tax On Text Messages