Q:

Google Play 30% transaction fee

Google support states that:
"For applications and in-app products that you sell on Google Play, the transaction fee is equivalent to 30% of the price.
You receive 70% of the payment. The remaining 30% goes to the distribution partner and operating fees."
I'd like to clarify the following:

If I'd like to upload an application to Google Play Store that's just an apk webview wrapper (so it's basically web-based app). If I set a download price, does the transaction fee of 30% still apply?
If I incorporate a Visa or PayPal transaction inside the app (not for buying in-app products but mostly for depositing and withdrawing money regarding sports betting and slots gambling), does the transaction fee of 30% still apply for this "money" movements?

A:

Transaction fee which is equivalent to 30% of the price applies to absolutely all applications (regardless their content) and in-app products that you sell on Google Play. You receive 70% of the payment. The remaining 30% goes to the distribution partner and operating fees.
Reference: https://support.google.com/googleplay/android-developer/answer/112622 
According to the Google Play Developer Program Policies:

In-app purchases: 

Developers offering virtual goods or currencies
  within a game downloaded from Google Play must use Google Play's
  in-app billing service as the method of payment. 
Developers offering additional content, services or functionality within another category of app downloaded from Google Play must use Google Play's in-app billing service as the method of payment, except: > 

where payment is primarily for physical goods or services (e.g., buying movie tickets, or buying a publication where the price also includes a hard copy subscription); or 
where payment is for digital content or goods that may be consumed outside of the app itself (e.g., buying songs that can be played on other music players).

Reference: https://support.google.com/googleplay/android-developer/answer/112622

