I would like to have live data that I can look at either on my phone or by possibly going through and installing multiple gauges.

In Scotty's videos he states that you should not keep the scan tool hooked up all of the time as it will cause problems eventually up to even breaking the ODBCII port.

So my question is - Is there a tool I can safely leave hooked up all of the time to look at/monitor data or do I need to start going through and installing real gauges for things.  I am mostly interested in basic items but more data is cool too.  My main interests I know have gauges that I can install such as:

Engine temp

Transmission fluid temp 

Oil pressure

Voltage

I guess I am answering my own question and should just install those gauges but your feedback is appreciated.