Advice on Arduino for Gas Flow Application

Hi,

As background check, I am familiar with this all but i have never implemented arduinos in my projects. Heard they're nice! As well as the second part of my question below is being asked with using a ardiuno in mind
So a brief description of my project is i have to create a device that will measure a certain amount of volume of air. Connecting to a PC can be the easy route for anything reason. I will be using a mass flow sensor; FS1012-1100-NG sensor by IDT, in case you are wondering

And as a bonus feature it can connect to a mobile to display things (which is part of my question)

I am deciding on arduino UNO or nano. Is there reason one would be better than the other, disregarding size and information on the specs? The use would be processing the data the sensor i doing and then displaying it onto a interface, PC/Mobile/Screen part of the body of the whole device; Each one would be a step up from the previous so i would start with what is easiest.

Also would using wifi or bluetooth be a better option when trying to connect the arduino to a phone (bonus path). My main path would be connected to a PC and assume a USB like connection can do that, might even attempt BT/WIFI in order to build myself up to a mobile version.

Thank you

Uno and Nano are essentially the same. If you limit yourself to what you have described, either would be fine. If you want to add on-board memory, local display etc., you will probably need a Mega, which has more memory.
Using Bluetooth enables you to use Bluetooth Graphics Terminal which, with Arduino, is a marriage made in heaven.
If you stay with PC, you should consider http://forum.arduino.cc/index.php?topic=437398.0

NANO 33 IoT
Is a new model with WiFi ability.
Faster and more memory than the older NANO or UNO boards