StripeBilling
Subscription billing and payments platform.
Net Suite
Cloud ERP for finance, inventory, and operations.
PayPal
Digital payments and checkout solution.
Stripe
Online payment processing platform.
FreshBooks
Invoicing and accounting platform.
Wave

Free accounting and invoicing software.
Xero
Online accounting platform for businesses.
QuickBooks Online

Small business accounting and bookkeeping software.
Lightspeed

Retail POS and ecommerce platform.
Square
Point-of-sale and payment processing system.