Research

Working Papers

The Case of Apple’s Restrictions on Super Apps: Is the U.S. Department of Justice Right?

(Job Market Paper; last updated: October, 2026)

The novel “super app” technology, which emerged in the early 2010s, enables app developers to run a single version of an app on different operating systems. Apple’s alleged practice of restricting super apps in the United States is one of the subjects of a recent antitrust complaint filed by the U.S. Department of Justice (2024). I present a model of a two-sided market with cross-side network effects to investigate two questions: why Apple restricts super apps in the United States but not in Asia; and whether its restrictions may adversely affect market competition and welfare in the United States. Furthermore, I show that whether these restrictions harm consumers and developers depends critically on whether consumers view platforms as highly differentiated or close substitutes, the extent to which restrictions on super apps increase consumers’ switching costs and decrease developers’ multi-homing savings, and the number of apps operating on each platform.

Cheap Talk with Costly Information Acquisition by the Receiver

(Last updated: October, 2026)

This paper examines the welfare implications of the receiver’s costly information acquisition in a cheap-talk model. I find that both a reduction in the cost of information acquisition and an increase in the informativeness of the information source can generate welfare gains, regardless of the welfare weights or whether receiver learning crowds out sender communication. Furthermore, a cost reduction improves welfare under broader conditions than an increase in informativeness.

Work in Progress

Interdependent Bargains with Downstream Competition and Vertical Merger

with David Sibley and Yihang Zhou

We examine interdependent bargaining where two downstream competitors simultaneously bargain with a common upstream input seller under both the Nash bargaining solution (NBS) and the alternating-offer (AO) protocol. We evaluate the competitive effects of a vertical merger between the seller and one of the downstream competitors. In the post-merger case, we establish a theoretical equivalence showing that each NBS under specific bargaining powers is equivalent to an alternating-offer bargaining outcome for specific discounting factors. This result highlights a critical limitation in the existing empirical literature: whenever estimated discount factors and bargaining powers violate this equivalence relationship, the empirical application of NBS lacks structural microfoundations.