PayPal - PayPal is the faster, safer way to pay online without sharing financial details, send and receive money or accept credit and debit cards as a seller
iA Writer - Minimal Design, Maximum Focus
Stripe - Online payment processing for internet businesses. Stripe is a suite of payment APIs that powers commerce for online businesses of all sizes. Use Stripe’s payment platform to accept and process payments online for easy-to-use commerce solutions.
MacDown - MacDown is an open source Markdown editor for OS X, released under the MIT License.
Payoneer - Whether making international payments, receiving funds, managing your digital business, or accessing capital, Payoneer opens your business up to the world.
MWeb - Pro Markdown writing, note taking and static blog generator