I am 99% positive that the EVO 4g lte supports the aptX bluetooth codec as i have purchased a pair of LG tone+ bluetooth headphones with the aptX codec and the sound is amazing! To give you an idea of what I mean, i normally use the Volume+ EQ from the Android market for my bluetooth headsets, but found that after purchasing the LG TONE + (or HBS 730s), i had to turn my Volume +EQ off as it was no match for the headphones without the EQ. Also, the LGs have a built in EQ that the user's guide says is rendered useless if your source is aptX capable. So, of course I tried to engage the EQ on my Tone+s to no avail. But, that still wasn't enough, I connected my LGs to another bluetooth phone (no aptx) and ....Voila!....the LGs EQ worked. So, by a process of elimination, i was able to determine that our EVO LTEs do, in fact, have the aptX codec and take my word for it...IT's AWESOME!