Airship announced today that it has acquired Apptimize, an A/B testing company whose customers include Glassdoor, HotelTonight and The Wall Street Journal.

Formerly known as Urban Airship, the more concisely named Airship has built a platform for companies to manage their customer communication across SMS, push notifications, email, mobile wallets and more.

It says that by acquiring Apptimize, it can help customers test the impact of their messages. That means integrating Apptimize’s testing capabilities into the Airship platform, but the company says it will also continue to support Apptimize as a standalone platform.

“By combining Apptimize mobile app and web testing with Airship’s deep insight into customer engagement across channels, marketers and developers can focus innovation on the most critical areas while creating the seamless end-to-end experiences customers really want,” said Airship president and CEO Brett Caine in a statement.

The financial terms of the acquisition were not disclosed. Apptimize had raised a total of $18.6 million from US Venture Partners, Costanoa Ventures and others, according to Crunchbase.

Airship says it will be bringing over 19 Apptimize team members (a little less than two-thirds of the startup’s total workforce) across engineering, customer service and sales.