I volunteer for a cable access TV show each week and at least every other week someone asks me if we have a mirror so they can check their hair or makeup. I ask them if their phone has a backward facing camera for selfies, then tell them to just turn it on and look into it and you'll see a "reflection" of yourself.
You can also use your phone as a police radar trap detector. There is a great little GPS mapping program called WAZE. The people who use it are called "Wazers." The success and value of this program is based upon how many people use it and report events to it. It uses your camera as a means of communicating with the program or app. You just wave your hand in front of the phone and Waze will ask "How can I help you?" If you see a police car sitting on the side of the road waiting to catch speeders, you wave your hand and say "Report police radar trap." That's it. Waze will mark the map at the point of the wave with a little police icon. When other Wazers come after you, they will be notified about half a mile in advance that there is a radar trap up ahead. You can see other Wazers on the map, too. So, if you see Wazers in front of you, hopefully they are reporting road hazards and you will be better prepared for them.
Now some people will think that this is an immoral or illegal use of technology but it isn't. The police set up radar traps to catch people speeding so they can punish them with a ticket so they won't speed because - speeding causes accidents and can kill. If Waze and former Wazers notify you that there is a speed trap half a mile up the road, you will slow down, thus, preventing accidents and killing people. So, what is bad about that? Oh, police use tickets to "tax" people to fill the town coffers. Send a donation to your town if you feel guilty.
Waze can also be used to warn people of disabled vehicles, pot holes, construction, red light cameras, driving hazards, dead animals on the road, debris, detours, heavy traffic, black ice, etcetera. Try it, I assure you you will get hooked. Just purchase some kind of mount for you phone so you can glance at your screen without taking your eyes off the road. Again, the software is voice activated so there is no reason to take you hands and eyes off the road other than an initial wave at the phone to get Waze's attention. You can also set it up so that you just tap the screen to activate it.
Waze is also an excellent GPS and mapping program and you can use it to find gas, directions, lodging, food or whatever your heart desires. Try it, it's free but does come with minor ads once in a while. When I stop for stop lights, an ad for a local establishment might pop up but will disappear when I begin moving again. If you live in a community where there are not many Wazers then the protection this software can offer won't be of much value to you. Try it though and get all your neighbors to try it. That way you will be protecting your community.