[AC Question]

When I send a longer than usual text message from my Samsung Galaxy to another Galaxy, it is delivered in one piece. If I get a longer message from others on the same carrier, but a different phone, it comes fragmented into more than one.

[Rukbat]

Depending on how the sending app is set up, messages longer than 140 characters (80 if your alphabet uses Unicode characters) are sent in one of two ways - either as an MMS file (no pieces) or as multiple 140-character texts (which can arrive in pieces). It's the sender's setting - nothing you can do except ask them to set their text app to not break long messages.