Updated. Apigee, a Palo Alto, Calif.-based API management platform and services company is buying San Francisco-based Usergrid, as part of its increasing focus on the mobile app business.  Terms of the deal were not disclosed.

Companies such as Netflix (s NFLX) and AT&T (s T) have been using Apigee to offer their application programming interfaces to developers. While most of Apigee’s initial efforts were focused on web and enterprise applications, the company (which was started under the name Sonoa Systems) has seen most of the developer focus shift to mobile.

When I asked Chet Kapoor, Apigee CEO if this acquisition was a change in direction for the company, he said that Apigee had been dealing with the shift to mobile for nearly a month. He said developers (including those in enterprises) are thinking about mobile apps before web apps.

Apigee, Kapoor says will offer the Usergrid and its own API management platform as a cloud-based service. With this acquisition, Kapoor says, Apigee will now be able to give enterprises and developers a simple, easy and scalable way to access the full range of APIs — enterprise APIs, public APIs, and, now with Usergrid, the core APIs that all mobile applications need.

Usergrid was started by serial entrepreneur Ed Anuff who most recently worked for Six Apart. Previously, he was co-founder of Widgetbox, a popular marketplace for widgets, and he was also co-founder of enterprise software company Epicentric, an enterprise portal software company. He left Six Apart to start Usergrid, a mobile app cloud platform with focus on user management. As part of the deal, Anuff will join the new company as a vice president.

Anuff started Usergrid to collapse the complex mobile-app development stack and allow developers to focus all their energies on client side presentation and application logic – aka what sits on the phone. He wanted to hide all the complexity – hosting, databases, storage, server-side application logic, API services and user provisioning – and offer it as a cloud service. The cloud-based mobile app development platforms are a hotly contested category and recent entrants like Parse have drawn a lot of attention.

Update: Apigee contacted us to clarify that the company is not, in fact, shifting away from the web in favor of mobile, since much of the company’s revenue already comes from mobile, and that the acquisition is an expansion of its business.