Best gas pipe sizing app?

[Leo21]

As above, which ones have you guys got and how do you rate them. First one to answer gets a "like"

 

[Mike Jackson]

Never seen the need for one it's not that tricky to size gas pipes.

 

[AlexGas]

Would you trust a Tomtom?
I keep it simple – pen and paper.

 

[Ermintrude]

Can generally make a guess on a quote for domestic . Anything bigger than 33 and 8m gets 28mm . Size properly if get job 28kw is about 12m of 22mm?

 

[kozak1968]

G.B Gas.co.uk pipe sizing app cost £5...... you can do sizing on job.