When sending a text message through Revere Mobile, certain considerations need to be made based on the length of the message and the characters that are included with in the message itself.  A message status will appear below an SMS/MMS message with a remaining character count, as well as any warnings or notices based on current content.  When using special characters, such as accented characters for Spanish messages, character count is decreased and a different message appears.  This is due to the character encoding necessary to send the messages with the characters specified.


When sending a text message, there are differences in how the message is encoded when using SMS or MMS.  MMS is automatically handled as UTF-8 text, which handles characters from languages outside of English, but also supports a number of different symbols, such as emojis.  SMS, however, is handled as GSM text, an older standard used by mobile carriers.  This encoding allows for a much smaller set of supported characters, trading flexibility for a smaller size.  When sending a message encoded with GSM, 160 characters are the standard maximum length (however, certain characters such as ‘[‘ and ‘]’ will count as two characters).  A way around this for SMS is to encode a message as UTF-8 before sending, which allows for many more characters but also restricts the character count to a maximum of 70 characters.

Currently, we support a subset of the GSM character set, defined by the characters listed below:
! " # $ % & ' ( ) * + , - . /
0 1 2 3 4 5 6 7 8 9 : ; < = > ?
@ A B C D E F G H I J K L M N O
P Q R S T U V W X Y Z [ \ ] ^ _
a b c d e f g h i j k l m n o
p q r s t u v w x y z { | } ~
£ ¥ Ø ø Å å Δ Φ Γ Λ Ω Π Ψ Σ Θ Ξ
Æ æ ß É ¤ ¡ Ä Ö Ñ Ü § ¿ ä €

When sending an SMS message that is encoded as UTF-8, one important feature of this is that the message only supports characters in the BMP (Basic Multilingual Plane).  This means that while a number of characters are supported from other languages, characters such as emojis (defined in the Supplementary Multilingual Plane) are not.  Characters outside the BMP require more space to store, which would further restrict the message length for an SMS message, among other challenges.

Using Special Characters in Revere Mobile

When sending an SMS message, the interface will inform you instantly when a character will cause a message to change from GSM to UTF-8, by changing the character limit to 70.  If the character is removed, the limit will return to 160.  If a character is used that is outside the BMP, a warning will appear indicating the character is not supported.  If that message appears, you can try and switch over to an MMS message, as it should be able to support all UTF-8 characters (however, MMS messages do cost more to send than SMS).

With the lower character limit, it can be challenging to convey the same message with half the space.  If you need to go over the 70 character limit, the system will allow this (though a warning will be displayed), and the message will be processed in the best possible way for given carriers.  AT&T, T-Mobile, and Verizon all support a feature known as concatenation.  With concatenation, your message will be sent as multiple messages in 70 character chunks, and reformed by the carrier in the correct order (appearing as one message).  When using this feature, you can bypass the standard limit, however, you will be charged for each of the parts sent individually.  Sprint is the only major US carrier to not support this feature, and messages will appear in the order they are received by the carrier, meaning your messages could appear out of order.