This makes it the best free scheduling software on our list for solopreneurs. You get unlimited appointments, multiple booking options, multiple CRM features, and integration with all of Square’s other software, including a fantastic point-of-sale system. Square Appointments has an interesting concept – everything in its offer is available for free, but only for one user. The scheduling software was acquired by Square in 2014. It was first devised by an independent company called BookFresh. Square Appointments is an appointment manager from Square, a financial services, merchant services aggregator, and mobile payment company in San Francisco.