AptX does make a huge difference in "depth" and dynamics of the sound, though discussion about particular brands is pointless. Apple in general (there was one MacBook pro as an exception) does not support AptX as they would have to cough up licence fees. Samsung top line phones (since S3 I think) do support AptX as well as number of other phone makers (including some Lumias).
AptX always needs to be licenced as this codec is prioprietary and that's why CSR (recently bought by Qualcomm) maintains a comprehensive list of all equipment with AptX support ever produced.
I know this because I was closely following the AptX progress since I bought Samsung HS3000 with this codec and was blown away with SQ when paired with my Note 2. In all these years since then I was buying or testing every small BT/headphone receiver that I could lay my hands on, including some not available outside Asia as this is incredibly handy device for commuting - listening to music or watching movies on the go.
The only notable exceptions that I've made were SoundBlaster E5 as it is so big that it's not really portable (try to pin it to your shirt's collar before you'll say I'm wrong
) and recently Noble BTS - as literally almost everyone who reviewed it was mentioning big bass roll off.
I was always wondering why there is so few devices of that type as the idea is brilliant. The only answer for me was that CSR requires licence fees, and devices without AptX were so piss poor that there was no point in using them (and I know as I've tried some including Sony and AudioTechnica branded)
My current king of the hill is AudioTechnica AT-PHA50BT with AAC and AptX and I'm really, really curious if XB10 can dethrone it.
We'll see tomorrow afternoon