https://www.reuters.com/article/us-tech-antitrust-apple/apple-agrees-to-testify-before-u-s-senate-on-app-store-antitrust-concerns-idUSKBN2BY0T8 >A senior Apple Inc executive has agreed to testify before the U.S. Senate on competition issues related to mobile app stores, days after panel leaders criticized the company for refusing to appear.