Is there a way for PayPal Business users to initiate a transfer to their PayPal account automatically. To put it another way, can we set something automatic on PayPal or use your API to program our app to do transfers?
You can use Rest API to receive funds, create billing agreements, as well as payout funds from a PayPal Account. While, there are no Rest API operations to add funds to a merchant's PayPal Account from their own bank account, merchants can receive funds from buyers that chose to pay using their bank accounts.
Here is a listing of different API Operations for Rest API: