So I picked up a Garmin GSC10 speed/cadence sensor after reading that my Samsung S4 (with Android 4.3 or later) has native ANT+ support, along with several other Android phones and iPhones. Then I found that Endomondo, even the free version I have, has built-in ANT+ speed and cadence support. Nice.
So off to the LBS and tested the GSC 10 and it worked. No need for a dedicated cycling computer now. Even the guys at the LBS were not aware this was possible.