What Android phones are ANT+ hardware enabled?
This list gives the most correct answer, as it gives "what Android phones have ANT wireless hardware" regardless of if the software piece has been turned on: http://forum.xda-developers.com/hardware-hacking/hardware/ref-devices-ant-hardware-t2879990

For which devices have the hardware and the software to support apps, the best place is the ANT+ Product Directory: http://www.thisisant.com/directory/filter/~/60/~/
However, this does not include devices which have not gone through certification to prove they work correctly, such as the Xiaomi Mi3 or OnePlus One.