IHS says that recent years have seen a drastic growth in smartwatch shipments - the market grew from 9.4 million units in 2014 to 149 million units in 2018. In just one year, shipments grew 42% from 2017 to 2018.
This rising demand for smartwatches has of course created a rising demand for displays. OLED displays are leading this segment - with around 80% of shipments in 2018 (the rest are mostly LCD displays). AMOLED display shipments were around 42 million and PMOLED shipments reached around 75 million.