Develop Reference

Split long SMS is concatenated wrongly on mobile ignoring the reference number

I use Cloudhopper library to connect to SMSC and submit messages.
I split long message in a standard way:
split text into small chunks of 134 bytes
generate next reference number
create UDH 6 bytes with ref number
send parts one by one
I have several connections open in transceiver mode to SMSC. If I use only one connection to send all the parts, then most of the time the messages are merged correctly both on Android 5.0.1 and iOS 8.4.1, though sometimes quite rarely the concatenated messages have the last part from the wrong message.
If I use different connections to send the parts, then most of the time messages are concatenated in a wrong way, usually the last part belongs to some other message. So it looks like mobiles don't honor the included reference number at all.
I know that if the reference number is the same and there are hanging old parts in the database on mobile then it might concatenate wrongly, but this doesn't seem to be the case in my tests since the reference number is sequential and controlled to be different for wrongly concatenated parts.
What could be the problem or how could I approach it?

SMS Manager send mutlipart message when there is less than 160 characters

I write a app which use SMS Manager. I use method sendTextMessage() but it isn't work. Now I am using sendMutlipartTextMessage() and it's work. But it's send multipart message when it is about 60 characters. This is normal? Everywhere I read than should be 160 characters. This is important to me because I must pay more.

The message character limit depends on the character bit-size of the alphabet you're using. For the standard GSM 7-bit alphabet, the character limit is 160. For an 8-bit alphabet, it is 140, and for a 16-bit alphabet, which sounds like your situation, it is only 70 characters. If you must send messages with special Unicode characters, like those in non-Latin alphabets, then you're stuck with the 16-bit alphabet, and its 70-character limit. If you can somehow convert the messages to the basic 7-bit alphabet, you will have the 160-character limit.

Why is a "#" being translated to "¿" when sent through SMS on Android 2.3?

I'm developing an Android application which sends commands to a remote equipment through SMS. The commands are all regular text messages, and some of them start with the prefix A##. To test the app I sent some "commands" to other phones using an Android 4.3 phone and also an Android 2.3 phone.
When I run the app on the Android 4.3 phone, the SMS on the receiving end shows just fine on any device, but if I use the Android 2.3 to send the commands they get received as A¿¿ on an Android 4.3 phone but arrive as normally as A## either on an Android 2.3 or an iPhone. On the target equipment (it uses a GSM modem) the message gets like A (character "A" plus two spaces - ASCII 0x20), so I suspect the sender is using a different encoding. What I find strange is the # symbol is not even an extended ASCII char, so I'm wondering why it would be encoded in some other charset than ASCII anyway.
Can anyone explain what is happening here? If the Android 2.3 device is really using another encoding, is there a way to force it to ASCII before sending the SMS?
The sending code is as follows:
#Override
public void sendCommand(String command) {
//TODO: Send SMS with 'command' as its text message
SmsManager sms=SmsManager.getDefault();
PendingIntent piSent=PendingIntent.getBroadcast(this, 0,
new Intent("SMS_SENT"), 0);
PendingIntent piDelivered=PendingIntent.getBroadcast(this, 0,
new Intent("SMS_DELIVERED"), 0);
String phone = txtPhone.getText().toString();
sms.sendTextMessage(phone, null, command, piSent, piDelivered);
}
Where the parameter command is always the concatenation of the prefix with some other text, like this:
String SmsPrefix = new String("A##");
sendCommand(SmsPrefix + "AT+DEACT");
UPDATE:
I had a hint from someone that problem might be related to the carrier, not to the Android system itself. I live in Brazil and my Android 2.3 device was using the carrier TIM, just the same as the iPhone we used. The Android 4.3 device was using the carrier Claro. What I found is that, if I get the TIM SIM card and put it on the Android 4.3 device the receiving end also shows the garbled #, so it seems the carrier TIM is messing up the SMS sent through their network. I will try the new suggestions from #PMunch below so we can possibly find a workaround, but we can be sure already it wasn't really some kind of bug corrected from Android 2.3 to 4.3.

Really seems like an encoding issue. It might be that you try to send as ASCII but the receiver tries to parse it in a different encoding. If you explicitly specify encoding on both sender and receiver end it should work.
EDIT:
This would get the character array and create a string from it all using US-ASCII encoding.
String newString = new String(oldString.getBytes("US-ASCII"), "US-ASCII"));
EDIT2:
Turns out GSM doesn't use regular US-ASCII, rather it uses it's own GSM alphabet. What seems to be happening is that the # (ASCII 0x40) is translated into the GSM alphabet directly as ¡ (Upside down exlamation mark, GSM 0x40). This won't affect regular text characters as they share the same addresses (same for the plus sign 0x2B). Then when converted back it tries to convert it frow what it assumes is GSM-alphabet to ASCII, meaning the 0x40 of the earlier # sign is now an upside down exclamation mark. This is a sign that does not exist in regular ASCII and is therefore replaced by an unknown character symbol, apparently an upside down question mark in Android 2.3 and a space in the GSM receiver. This lack of conversion from ASCII to GSM seems to have been fixed between Android 2.3 and Android 4.3.
If you try to specify to Android that this is an ASCII string by using new String ("A##","ISO-8859-1") it might do the conversion in it's own. If not you might have to do it yourself (Something like this might help). If # is the only special character you need to support then you could of course encode that single character yourself(\0\0 for ##).
EDIT3:
Edit2 included multiple actions, what did you try? To explain the whole GSM/ASCII thing:
ASCII uses it's first 32 characters as control characters. These characters were deemed unnecessary for GSM and so they were replaced with other characters. The null character, on computers used to terminate a string, is not used for text messages. They are set at 140 octets and any empty space is simply filled with filler characters. So the null character 0x00 in ASCII is used for something else, the # character. If you look at the GSM alphabet and the ASCII alphabet you will see that the 32 first characters are replaced by Greek characters and some others. If you look at the remaining characters they are mostly in the right place, the # character is one of the ones that aren't. If you for example try to type in _ you should get similar results. When you say that # comes out as A do you then mean that A## becomes A or that it becomes AAA? I also found something interesting while looking through Unicode conversion supplied by Unicode Inc.:
0x00 is NULL (when followed only by 0x00 up to the
end of (fixed byte length) message, possibly also up to
FORM FEED. But 0x00 is also the code for COMMERCIAL AT
when some other character (CARRIAGE RETURN if nothing else)
comes after the 0x00.
So if you tried to send only A## then the two last #s might be interpreted as padding characters instead of # characters. Regardless it seems like the carriers in your area does some conversion between them, have you tried to send the characters with sendDataMessage as raw data bytes? The function byte[] stringToGsm7BitPacked(String data) throws EncodeException from telephony.GsmAlphabet should help convert your string to the GSM alphabet.

Phone number with and without international prefix

Suppose I receive an SMS from a contact. If I then extract their phone number from the SMS, this phone number will also have the international prefix.
Now suppose that I want to send an SMS to this contact but I avoid writing the international prefix. Out of the box the two messages won't appear in the same thread. How can I show all the messages coming from and sent to a contact, when they differ only in the prefix?

define a constant M in which you put the minimum match length and you compare last M digits from both numbers.

Special characters in Android sms

I've observed this issue for years now, not knowing where it came from. I am concerned that this bug is still observable in the new versions of Android, in 2011, and I hope you can finally help me to fully understand it, if not solve it.
Let's consider the given (real) situation. Mister "A" is using a custom SMS/MMS app from Sony on his Xperia Arc (official 2.3.3). Mister B is using the android SMS/MMS stack app on his Milestone (Cyanogen 6.12, unofficial 2.2). Both of them use Android in French (if that matters).
When A sends a sms to B containing special characters like "ç", "ê", B receives a message with these characters replaced by a space. Characters like "é" are working fine though.
When B sends the sms to A, everything works fine.
When A sends this sms to himself, everything works fine.
Conclusion : this is not the mobile provider's fault since it works in one way and not the other.
So, I guessed at first that something was wrong with A's custom app. Replaced it with the apk from B's phone. Everything remained the same. I decompiled the app and I didn't find where the encoding of the sms string was done. I concluded the bug is not coming from the app, but from the way Android encodes the strings...
I ran another test :
I wrote an sms with only standard characters, something like 250 characters in 1.5 sms. Then, I append a "ç" to the sms.
On A's phone : the counter says it consumed 10 characters.
On B's phone : the counter says the sms now takes 3 sms : the string size doubled !
Conclusion :
On A's phone, the default charset includes "ç".
On B's phone, when "ç" appears, the charset changes and each character needs then twice the original space.
(Or am I missing something ?)
Questions :
Why different version of Android aren't using the same default charset ?
On Android, are these default charset depending on the rom, for example ?
Can we configure/change these charset somewhere (in the menu or directly on a rooted phone) ?
Is there another easy way to fix this ?
Any help, explanation or experience is welcome :)

You are suffering from encoding problems. From the description it looks like 'A' is sending data in one charset and not including information about what charset that is. The root cause is that to pass extended (non-ascii) characters between two systems they have to agree on an encoding to use. If you are restricted to 8 bit values then the systems agree to use the same codepages. In SMS there is a special GSM codepage for 7 or 8 bit encodings or UTF-16 can be used which uses 2 bytes to represent each character. What you see when you enter 250 characters followed by a single extended character shows you what is happening in the application. An SMS message is restricted to 140 octets. When you are using an 8 bit encoding your 250 chars fit into 2 messages (250 < 280) however once you added the "ç" the app changed to using UTF-16 encoding so suddenly all your characters are taking 2 octets and you can only fit 70 characters into a message. Now it takes 3.5 SMS messages to transfer the entire message.
On Android the decoding of the SMS message is part of the framework telephony code in SmsCbMessage.java. It works out the language code and encoding of the message body. If this is incorrect (the message was encoded with an english codepage but uses french extended chars) then you can get odd characters appearing.
You are right that this is not the mobile network at fault. I suspect it is phone A's messaging application although it is possible that Android is failing to correctly identify the encoding of a valid SMS. I wonder how it works between A and an iPhone or some other manufacturers device.

I have encountered the same problem when I had to show a few special characters in an sms unicode app. The method I used was take the string that I need to send as sms, run it in a for loop to take each character , find its ascii code , use that integer value to encode that string using a delimiter. This string can be sent as sms, which needs to be decoded using the same delimiter that is used for sending, then convert each ascii code char in it to characters (language specific), form a string by appending the converted chars. This text will be same as the one that was sent as sms.
Regards