I highly doubt he had eyes on you :-)

The fact that he goes out of his way to talk about a very special iPad leads me down the path that maybe he's signed in to your iCloud account? If so, he's watching iMessages and any activity to contacts/calendars/reminders/etc...

A few clarifications that might better help us:

1. Is there some sort of bet or challenge?

2. Were you intentionally hiding?

3. Has your friend had recent physical access to any of your devices?

Boy have I hit rock bottom responding to this...fucking insomnia :(