SAP acquired CoreSystems, a Swiss firm specializing in customer service software, on undisclosed terms. It's the latest in a string of related deals including Callidus, Hybris, and Gigya. CoreSystems helps manufacturing, energy, high-tech and telecom firms to "crowd source" their field service operations, allowing them to cut response times by field service technicians or contractors for new installations or maintenance calls, reducing the time customers are left waiting at home. CRM software has already overtaken back-office enterprise resource planning (ERP) tools, where SAP is dominant. CRM will top database management software in 2018 to become the biggest single category of business software, Gartner predicts. The research firm has estimated the CRM market will double in size between 2016 and 2021 to nearly $66 billion, while ERP will grow two or three times slower to around $39 billion over the same five years.