Bowie appeared on Canadian band's latest album 'Reflektor'
Artist on course for Number One with new album 'Blackstar'
Bass player described Bowie as "the most beautiful, the best"
Music icon dominates charts following death
British artist assures fans that he is still alive
Blondie toured with Bowie and Iggy Pop in 1977
@TheTweetOfGod was one of 172 users Bowie followed on the social media site
Sources close to the late singer reveal details about his ill-health
The pair recorded 'Just Dance' together in 1983
Fans led mass singalongs and celebrations