Can you retrieve data from a phone that wont turn on? but lights up the home screens.
If the data has been saved to the memory card you can pull it and retrieve it on your PC. Some phones automatically save data to the memory card, others don't.
Depends on the phone's make and model... and age. You can always call the phone company and ask them, but they're little help.
Find a data recovery program on your computer, plug your phone to it and run the program.