Download the APK file, manual, and other details from here.
The software seems to cover many of the same functions, and modes, as its big brother Windows version.
I have only had a short time to play around with this tonight, but soon after I downloaded the APK on to my phone, a quick easy configure it was up and running within 5 minutes.
This now opens the door to cheap home and portable operation, using FLDIGI's modes likes PSK31 etc. Using simple Android tablets and Android PCs available from the likes of ebay for less than £50!
My 7" Android PC below, which should be suitable for use with FLDIGI.