The best replacement for hdx is hd.

The best alternatives to hdx are rated as following:
★★★★★  hd
★★★★  ipad air
★★  hd kindle
★★  nexus
★★  hd native
★★  fdx
★★  ipad mini
★★  nexus 7
★  ica
★  pcoip
★  tdm
★  unitiserve
★  nexus 10
★  kindle fire hd
★  rdp
★  ipad mini retina
  ndx
  popcorn hour
  hd tdm
  hd vudu
  retina
  nexus 7 2013
  pc-over-ip
  remotefx
  numark cdx
  bluray
  roundup
  nook hd
  dv7
  ripcord
  samsung tab 3
  google nexus 7
  nook

Your alternative for hdx is not listed? Suggest!
Speaking about hdx, one probably shouldn't forget about 192.

Other search terms related to hdx and their ratings are:
★★★★★ 192
★★★★ lynx aurora
★★ xenapp
You have in mind a companion for hdx and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of hdx in all years. Click on graph for more.
hdx
hd
ipad air