The most common and most likely answer to this crossword clue is the 5 letter word PAGER
I've seen this crossword clue in The Daily Telegraph
P
A
G
E
R
More clues leading to the result PAGER
- Publicity about period radio device
- Secretary right, say, to pick up message on this?
- Wireless device turned on before interval
- Alert Pompeo and Rudy for starters — time to get involved
- . Prince about to get on alert system?
- Empty gesture welcomed by standard caller
- What’s used to summon grapeshot
- Signalling device for train attendant at railhead
- Communication device for one in charge northwards
- With which to contact spin doctor
Buddy explains!

The straight part
We know that "Electronic device" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case electronic device = pager.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 PAGER mean?
PAGER noun- A wireless telecommunications device that receives text or voice messages.
- A computer program running in a text terminal, used to view (but not modify) the contents of a text file moving down the file one line or one screen at a time.
- (in combination) Something (a document, book etc.) that has a specified number of pages.