Google said Thursday it has entered into a definitive agreement to acquire Apigee, a provider of application programming interface (API) management.

APIs are the mechanism developers use to interface and integrate with outside apps and services, and are vital for how business gets done today in the fast-growing digital and mobile marketplace.

They are the hubs through which companies, partners and customers interact, whether it’s a small business applying online for a loan or a point of sale system sending your warranty information to the manufacturer.

Apigee is already used by “hundreds of companies,” Google said, including Walgreens, AT&T, Bechtel, Burberry, First Data and Live Nation.

Walgreens, for example, uses Apigee to manage the APIs that enable an ecosystem of partners and developers building apps using Walgreens APIs, including the Photo Prints API (enabling mobile app developers to include the ability for their app users to print photos at any Walgreens store), and the Prescription API (enabling users to quickly order refills of prescriptions right from their mobile app), said Google.

“The transition toward cloud, mobile and digital interaction with customers and partners via APIs is happening, and fast,” said Google Senior Vice President Diane Greene in a company blog post.

“It’s happening because customers of every stripe — in the consumer realm and in the enterprise — are demanding it, and because it translates to engaging and valuable businesses,” she added.