QML display different on iOS & Android ~ QChart

[SamGrant]

Same App on iOS & Android.

On one page of the app, Android shows QChart graphs as designed (80% of parent width), but iOS downsizes them. On all other pages, all objects are displayed as expected on both platforms.

I've checked on iOS 9, 10 (iPhone 5 & 6) and Android 5, 6, 7 (Moto Droid Turbo, Droid Turbo2, LG G3).

Android page:
http://beentheresailedthat.com/app/android.png

iOS page:
http://beentheresailedthat.com/app/ios.jpg

Any ideas?