The Billogram Ruby SDK by Mark Birman allows to integrate invoicing services into applications. Installation is available. To configure the client, developers can insert username and password. Resources include endpoints with invoice, item, customer, event, settings, report, and logotype.
Pactas, recurring billing solution provider, offers the Pactas API that allows developers to include Pactas functionality within third party apps and websites. Any need for recurring billing (e.g. carsharing, music flatrates, cloud services, etc.) can be simplified and streamlined with the Pactas solution. Pactas enables users to manage subscriptions, track payments, and map pricing. Access to the platform can customize to each users' situation depending on need, resources, and integration opportunities.