I have Paypal Account. can I integrate Paypal Payment Gateway only using Paypal Account or should I need to purchase Braintree Account too?
To integrate PayPal Checkout, you only need a PayPal business account to receive the payments. From a native app you can use the new Native Checkout SDK.
Braintree Direct is a separate gateway product, with other features. The Braintree SDK, which does not require a Braintree account for us with only PayPal payments, was also useful for integrating PayPal Checkout in native apps before the Native Checkout SDK was available.