So occasionally someone will ask to use my phone just to use my camera. The last time this happened it was at work, but it can be a friend or relative that just needs a quick picture of something. While this question is mainly for camera use, I suppose it can be used for anyone wanting to use your phone for internet, phone calls, or anything else.
So when this guy asked to use my camera at work, it was because his was broke and he needed a quick picture of a part to send a customer. I just let him take the picture then I sent it to him in an email. However, before I gave him my phone I immediate began worrying about what photos I had on there. Since he was standing right there waiting for me to hand him my phone I didn't have a chance to check so I took the risk of just giving him the phone.
Now I have a girlfriend that likes me to take a lot of risque photos of her. What can I do to avoid the awkwardness if someone needs to use my phone? I don't want to say plainly "no" because I feel like that's rude.