Just off the top of my head, you could text it to someone or make an audio recording and send it to someone. I have to assume there will be a note taking app if there wasn't one already that would allow you to dictate or type out notes that could include personal information. Maybe you saw someone's address and went to Maps and dropped a pin there or you saw someone's phone number and put it in the contacts.
At my job, we deal with financial information and as part of our contracts the institutions we are contracted with make it very clear we can not use our phones at our desks because of the sensitive information we deal with. I pointed out to my boss that if I wanted to steal someone's information I could just write it down on piece of paper and take it with me and I got kind of a resigned "what are you going to do?" look.