keep finger on the pulse of
keep (one's) finger on the pulse (of something)
To maintain an awareness of current trends and happenings in a particular place, situation, or environment. Sara always keeps her finger on the pulse of city's nightlife, so I would ask her where you should have your birthday party. You've got to keep your finger on the pulse if you want to remain relevant in this industry.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
keep one's finger on the pulse of something
Fig. to monitor the current state of something frequently. I have to keep my finger on the pulse of the city if I want to be a good reporter. It is hard to keep your finger on the pulse of Washington, D.C., but a U.S. senator must do it.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.