Yet another USB Meter. AVHzY CT-2 (ChargerLAB POWER-Z KT001, Kotomi Premium). It can both store curves offline or be used together with PC application.
PC Application
not as good as ChargerLAB Power-Z KM001 has. Poor visualization and export options. But at least it has English language interface. Support site available at http://www.avhzy.com/ 
Some additional options in software are:
Logo customisation
Device screen screenshots
PD Listener
Price: ~70$