The most common and most likely answer to this crossword clue is the 4 letter word FONE
I've seen this crossword clue in Independent
F
O
N
E
More clues leading to the result FONE
Buddy explains!
The straight part
We know that "mobile (phone) texted (in TXT SPK)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mobile (phone) texted (in txt spk) = fone.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does FONE mean?
FONE noun- An enemy.
- A unit of energy equal to 1044 joules.
- Phone