Just wondering if anyone uses their phone to keep notes at table. Things like what villians do, showdowns you see etc. Is there software for this?

I use poker journal to track my stats and will take notes for hands to post in that app or sometimes in 'notes' app on iPhone. I don't take constant notes as it would take away from paying attention to the game.

Just pay attention to the game. Don't write notes on players.

You're not going to see enough hands to construct concrete ranges.

Just figure out who is loose, who is tight, who is limping a lot, who is nut-mining, who is looking to gamble, who is tilted, who is winning, who is losing, who knows the dealers, who is drinking booze, who is bluffing, who is never bluffing, etc.

yes I do. not about players but about hand histories on big hands or tough/uncertain hands so they can be reviewed later.

I have never seen any apps for this so what I do is open up a new email and email the information to myself, so each hand will be separate and they wont be erased by accident.

If I see an interesting hand that goes against my perception of one or more regulars, whether im in the hand or not, I walk for a few hands and make a voice memo. Much easier than trying to type in the notes sectoin of poker journal. It happens once every session or so.

I have over 100 voice memos and i x-fer them to my desk top from time to time to further analyze.

I usually don't bother unless the hand was shown down.

Things i look for:
Tells of any kind.
Strange lines taken, for value, semi-bluff, air barrels.
Big Bluff lines made by regs.
Pre-flop 3bet ranges.
Flatting with monsters when the pot is already large, especially on the turn.
How people play JJ and TT pre-flop from any position.
And more, basically anything that helps me range regulars better.

I don't worry so much about rec-players as they aren't generally very tricky or around often enough to worry about it. I adjust to them on the fly when they make a play that warrants reclassification.

I don't keep notes on players, it was useful online but typically easier to remember people live if you encounter them multiple times. Also not enough hands to make much of a difference.

I do sometimes use Evernote for hands I want to think about later. Even then just the barebones to jog my memory. I've got a photo memory so it doesn't take much.

nope

I just try to be as observant as possible while playing and generally will remember from past sessions how some regular villains will play. I do take up to a couple HHs, on my phone or a just a mental note, from a game if i think it is an interesting spot.