[lazerwalker]

FWIW, Apple's 30% cut doesn't apply. You can't use Apple's IAP system for physical goods.

[adrianmonk]

Same story on Android. Google Play's in-app billing is for digital goods only. (See the over here: https://developer.android.com/google/play/billing/billing_ov...)

You can use Google Pay (note no "l" in second word) for physical goods, although I think you can collect your own payments if you prefer.