Apple Pay commission fee is much lower than 30% for In-App purchase. It seems it is more worth to use Apple Pay.
I use now In-App purchase to enable remove ad from my app. Do you think I can replace it with Apple Pay?
No, Apple Pay is for physical goods or services only.
Apple Pay or In-App Purchase
It is important to understand the difference between Apple Pay and In-App Purchase. Use Apple Pay to sell physical goods such as groceries, clothing, and appliances. Also use Apple Pay for services such as club memberships, hotel reservations, and tickets for events. On the other hand, use In-App Purchase to sell virtual goods such as premium content for your app, and subscriptions for digital content.
Not at all. As @grgarside told Apple pay is a kind of replacement for credit cards and is only for physical goods.
Additionally, If you read the iOS Paid Applications agreement, you will see the following about commissions:
(a) For sales of Licensed Applications to end-users located in those countries listed in Exhibit B, Section 1 of this Schedule 2 as updated from time to time via the iTunes Connect site, Apple shall be entitled to a commission equal to thirty percent (30%) of all prices payable by each end-user. For purposes of determining the commissions to which Apple is entitled under this Section 3.4(a), the prices payable by end-users shall be net of any and all taxes collected, as provided in Section 3.2 of this Schedule 2.