TripAdvisor acquired a San Mateo, California startup ZeTrip, which offers Rove, a personal journal app founded in 2011.

The terms of the transaction, which occurred last month, were not disclosed.

Rove describes itself as an “automatic journal to remember your best memories,” and gives users the option to add notes and “curate photos.” It competed in a crowded app space that includes everything from Foursquare to Findery.

One interesting aspect of Rove’s technology, which TripAdvisor acquired, is that it is touted as optimizing battery use.

“We optimized our algorithm to minimize battery drain when you are stationary or moving fast like driving a car or flying a plane,” the app description says.

The three-person ZeTrip team joined TripAdvisor’s mobile team in Palo Alto, California. It is not clear if Rove will continue as a standalone app.

“We are pleased to welcome the innovative ZeTrip team to the TripAdvisor family,” said Adam Medros, senior vice president, global product, TripAdvisor. “The team will be a valuable addition to our mobile group and we look forward to integrating the company’s technology to further enhance the experience for TripAdvisor mobile app users.”

TripAdvisor has acquired other small, lightly used apps in the past, including photo app Tiny Post. In 2014, TripAdvisor spent at least $352 million on acquisitions, the largest of which was tours and activities giant Viator for $200 million.