TRRS Phone Jack Madness

Projects General Guidance
1

Hello. I am working on a little project, and I would like to use a TRRS phone jack to connect to some sensors.
I was hoping someone might be able to comment on which parts of the plug should be +V and GND?
I know it is generally not recommended to carry power over a phone jack because of the possibility of shorting something as it is plugged in and out. Maybe if GND or +V was position 1 on my diagram it would work?

Also, I want to be able to switch from TX, RX to two analog pins, and switch from +5V to +3.3V. What would be best to use in order to select between 2 lines as I have shown in my diagram? Mux? Shift register?

Thanks for your help!

Edit: I forgot to mention that weird pin 5 is a tip switch. Somehow when something is plugged in something happens. The jack is offered with or without a tip switch. I really don't know much about them besides being able to detect whether something is plugged in or not. Anyway here is the datasheet in case someone can explain if I should use it or not. http://www.cui.com/product/resource/digikeypdf/sj-4351x.pdf

2

The tip switch is only closed when there's no plug in the socket. If you can make use of that facility, go for it. I wouldn't use a plug like that for power for the reasons you stated. If you're not going to pass much power through it, why not use a MicroUSB plug and socket?