The most common and most likely answer to this crossword clue is the 4 letter word IPAD
I've seen this crossword clue in Independent
I
P
A
D
More clues leading to the result IPAD
- The cheapest promotion for this tablet?
- Tablet — one a day, containing phosphorus
- Painted a picture, retrospective displays a tablet
- Knock back some speed, a pill or a tablet
- Tablet swallowed – a pint’s knocked back
- Apple product paid off
- Smart P.C. paid with one up-front?
- Address publicity for computer
- Tablet yours truly had to swallow every year
Buddy explains!

The straight part
We know that "tablet" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case tablet = ipad.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.