Salesforce1 Platform gives Salesforce developers at all skill levels good options for building mobile apps.
Salesforce.com started as a cloud service for sales force automation. The company added a cloud-based development platform, Force.com, with a Java-like language (APEX), and went on to acquire the Heroku PaaS and a number of other services.
Today, Salesforce.com is the acknowledged 800-pound gorilla of SaaS for a number of business application areas: not only sales force automation, but also marketing, customer service, community building, business intelligence, B2B prospecting, and collaboration. Over the last few years, Salesforce has been building out its mobile strategy.