Joe Caiati, writing for dot info, digs into the completely visible diagnostic info found on each of your iOS devices.
Before you read the linked article, take a second and go to:
Settings > Privacy > Diagnostics & Usage
On the page that appears, tap:
Diagnostics & Usage Data
Tap one of the entries on this list. You’ll see a somewhat cryptic diagnostic record, full of information that can help Apple or an app developer diagnose a problem that happened on your iOS device.
If you have even the slightest interest on what this all means, take a read through Joe’s excellent article. Great stuff.