Matias Duarte is a Chilean computer programmer who currently works at Google responsible for the multiple UI revamps of Android: Holo and Material Design. He previously worked on HP WebOS before coming to Google.
“Our Lord DuARTe” is the running gag of /r/Androidcirclejerk on reddit since the days of Android 3.0 Honeycomb and Android 4.0 Ice Cream Sandwich when his UI decisions really started coming into effect.