iPad screen shattering (real or fake)?

I'm fairly new to After Effects and I was wondering what the workflow was for getting a video closeup of something like an iPad or device hitting the floor and the glass screen shattering.

• Does the device actually have to be dropped and really shatter in a closeup caught on camera?
• Or can I drop the device while getting the closeup and use After Effects to make the glass look like it's shattering in slow motion?

Thanks so much.