Squareup is an app designed for businesses to create invoices for customers and clients. After creating an account, you are able to send invoices via email, text message, etc. Clients are able to access their invoices once they have created an account with Squareup. Oftentimes customers and patients try to avoid creating accounts. If you are interested in an alternate invoicing option that does not require users to download apps and create accounts, consider using Transact. Transact is an invoicing company that has taken on a different approach to online transactions. Instead of an app, or the requirement to create an account, customers are able to bill pay via SMS. A text message would be sent by your business to your customer that contains a link. By clicking the link, customers are able to quickly pay. They will not need to create an account, download an app, or sign in to an account. Customers simply click the link, review their bill, and pay.