Unfortunately, Chrome for Android doesn't support extensions [4]. But if you have a rooted device, you can block ads/trackers/etc. across all apps via AdAway [5], which manages a custom HOSTS file for you.
[1] https://www.ghostery.com/en/download
[2] https://github.com/gorhill/uBlock/issues/524
[3] https://github.com/gorhill/uBlock/issues/556
In addition to the extension working on Firefox for Android, Ghostery has it's own browser:
https://play.google.com/store/apps/details?id=com.ghostery.a...
It's pretty new and has some key features that are still in development, but it's getting there.
I know Google is not making things easier[1]. Before every app that used WebView had it. Now Opera is alone with this feature on Android. Implementing it would give you a nice competitive edge and make many users happy. Somehow Opera is able to to do it super elegantly with WebKit code.
[1] https://code.google.com/p/android/issues/detail?id=62378
WRT Firefox, it does not play nicely with Google services, like Gmail. WRT, browsers...I have tried many of them under the sun and all of them have a consistent disadvantage over Google, that is, speed.
I've got many lay users friends who still look for an Ad blocker out of the box, for their mobile devices. I have hope from Ghostery and uBlock makers, fingers crossed.