SMS, MMS, or multiple MMS for long messages

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I just migrated from a Samsung U40 flip phone (not a smartphone) to a Moto G running CyanogenMod 12.

In my Samsung, when my text message was long, it showed up as an MMS message (like a cartoon picture of a short strip of film). I am in the dark about how long messages are handled on the Moto G. From surfing the web, I found that long text messages are often sent as multiple short text messages, and they don't always arrive at the destination in the right order. The limit on 1 text message is either 140 or 160 characters, depending on whether each character is encoded as 7 or 8 bits.

What does the bits/character depend on? Is it the OS, the messaging app, the air protocol, or the carrier? How can I tell whether I'm encoding characters as 7 or 8 bits? That tells me what the single-message length limit is: 140 or 160. I can't tell on my Moto G because all messages appear as a single unbroken sequence of characters, even when the message is much greater than 160 letters. This is from test messages sent to myself.

Also, is it possible to determine whether incoming and outgoing messages are sent as SMS or MMS? The Moto G simply shows each message as a dialogue balloon. It doesn't show an icon that distinguishes between SMS and MMS.
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andymhancock

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Posted 3 years ago

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Timo Tuokkola, Mobile Master

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It should be possible to change the settings for outgoing messages, but I'm pretty sure that the format for long messages is determined exclusively by the sender's phone.
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andymhancock

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OK, thanks. If you don't mind, I'd like to leave this question "unanswered" for a while in case someone can shed some light on the details.
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Levis, Employee

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Hi,

On modern phones such as the Moto G, long text messages are usually sent as regular text. The messages are broken up into 160 character increments, but usually appear on the receiving phone as one big SMS. In rare cases it might show out of order (this depends on how the carrier handles the message headers which has the page count for the messages).

Regular alphanumeric characters are usually in 8 bits. Where the bit changes is for special characters such as accents for languages such as French. These characters can increase the bits as well as the character count of a message. This means that you can type what appears to be a 60 character message with lots of accents that actually shows up on the SMS servers as 160 characters because of the change in bits to 16 bit from 8 bit.

There is generally no indicator on Android Smartphones that tells you that you are sending a regular text message or Text as MMS. But we have tested messages with over a thousand characters that send as regular text without getting converted to text as MMS (broken up into 160 character trunks once they hit the network).

Hope this helps! :)
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andymhancock

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Indeed, it does. Thank you so much for such a clear explanation. It depends on both the phone and the carrier. And so much for the 7 vs. 8 bits. It's 8 bits or more.

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