The best replacement for ube is purple yam.

The best alternatives to ube are rated as following:
★★★★★  purple yam
★★★★  taro
★★  yam
★★  wemo
★  purple sweet potato
★  beni imo
  okinawan sweet potato

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

Other search terms related to ube and their ratings are:
★★★★★ malagkit
★★★★★ biko
You have in mind a companion for ube and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of ube in all years. Click on graph for more.
ube
purple yam
taro