chrome doesn't appear to have extension support? is that right?
and if so any way to get adblock or similar on chrome or another browser.
If you want to stick with something like Chrome, and use Chrome sync:
There's #NoChromo based on chromium 51, but I find it sometimes crashes:
http://forum.xda-developers.com/android/apps-games/app-nochromo-wild-browser-appears-t3130776
The previous v42 was perfectly stable for me however.
Alternatively, RSBrowser is based on CAF 46, which is a chromium 46 build optimised for Qualcomm SoC devices, but I sometimes find the page can get "stuck", but can be fixed by going to a different site:
https://play.google.com/store/apps/details?id=com.rsbrowser.browser
Both aren't perfect in adblocking however.
If Chrome sync is not important:
This is the official ABP browser based on Firefox:
https://play.google.com/store/apps/details?id=org.adblockplus.browser
Or, just use Firefox with uBlock Origin, which I find is the best browser for ad blocking.
There's also Dolphin browser with their adblock addon, but this browser's performance has gone pretty down hill.
I think there's adblock addons for the Samsung browser as well, if you have a Samsung phone.