By the HHI, Apple absolutely has a lock on the market. https://en.m.wikipedia.org/wiki/Herfindahl%E2%80%93Hirschman_Index https://en.m.wikipedia.org/wiki/Herfi

By the HHI, Apple absolutely has a lock on the market. https://en.m.wikipedia.org/wiki/Herfindahl%E2%80%93Hirschman_Index https://en.m.wikipedia.org/wiki/Herfindahl%E2%80%93Hirschman... With 53% market share, Apple alone contributes over 0.25 to the HHI. 0.25 for the entire market is regarded as highly concentrated.