I don't know if anyone has had this bug before but I have had it twice. I have had 2 of my memo's deleted by the phone accidently. What happens is when you tap a memo to open, sometimes it displays blank for a few seconds before it can show the actual info in the memo. If you swipe back on the gesture window while the memo is blank, the phone thinks that the memos is blank and it deletes it. Watch out for this one, I have had my workout log deleted twice because of this.