Blowpipe Lite by Silverglance Software enables rapid sizing of low-flowrate HVAC pipes (max 20 gpm / 1 kg/s).
Calculations also include pump motor sizes, pipe expansion, weight and heat transfer. The app may be upgraded to the full version, with no restrictions, by in-app billing.

Blowpipe Lite operates in either metric or imperial units, using calculation methods common to UK, Europe and USA, and with international pipe data.