Based on a sample of 120 undergraduate finance courses that were offered in the U.S. in fall 2014, we have compiled a list of the most popular finance textbooks in each subject area (with their market share):

Corporate Finance or Financial Management

28%: Ross & Westerfield: (Essentials of/Fundamentals of) Corporate Finance
20%: Berk & DeMarzo: Fundamentals of Corporate Finance
16%: Brigham & Houston: Fundamentals of Financial Management (standard & concise)
8%: Brealey & Myers: Fundamentals of Corporate Finance

Accepi currently offers problems tailored to the Ross & Westerfield and Brigham & Houston textbooks, i.e., terminology and solution approaches follow the book.

Investments

67%: Bodie, Kane & Marcus: (Essentials of) Investments
13%: Jones: Investments
8%: Jordan & Miller: Fundamentals of Investments

Accepi currently offers problems tailored to the Bodie, Kane and Marcus book, i.e., terminology and solution approaches follow the book.