When Geronimo surrendered, reportedly a small group of apache escaped down to the remote Sierra Madre Mountains of Northern Mexico. Violence with them have been recorded as late as the 1930's and reports/rumor as last as the 1950's still persist. One report has them finally assimilating with the Raramuri (Tarahumara). 

So are they extinct? Watch the video and you decide!

Here is a 25 minute video on some of the Bronco Apache history. Viewer be warned, violent and sad. 

"Apache Extinction | The Secret War to EXTERMINATE the Last Free Bronco Apache" from the YouTube channel, Dates and Dead Guys

https://www.youtube.com/watch?app=desktop&v=FmiJxpttY_8 

Video and pictures credit to the author, "Mr. O"