I have a task, I need append to my client project Apple Pay. But we have integrated payment system Paypal. I researched Paypal SDK and found official information about stopping support PayPal SDK in 2013 and then below advice, use Braintree SDK. For using Braintree SDK I need create account in official web-site. where me need upload certificate and on page below a sow public and private key, merchantID. My question, if I integrate Braintree SDK on my client application I can use PayPal gateway for my Braintree SDK. If it real I will be grateful you for link on information.
Braintree definitely supports processing both Apple Pay and PayPal payments. For PayPal, you'll end up using the PayPal Business Account that you already have setup.
I recommend signing up for a sandbox account to test the functionality. Once you've signed up for a sandbox account, Braintree's developer docs have information on how to integrate PayPal and Apple Pay into your web/mobile app.
If you have any further questions while testing an integration, I highly recommend contacting Braintree's Support Team.