Problem view in chrome is : (you can see the fonts are too small)
there is some missing fonts error . But I put that fonts in path will remove it on apk --prod creation .
You must choose one font from customer. if it you have .otf file you must create .ttf and .woff in online conversion tool.
If fonts are Purchasable make sure you purchase it or user free versions available.
then create .scss like above fonts folder (\node_modules\ionic-angular\fonts) roboto.scss on your own.
Note: Name it as your own and give same name at (@import “tradegothic” here.