The U2 frontman had to undergo surgery and therapy following last year's incident
The secret acoustic set took place at Grand Central station on Monday (May 4)
A weeks worth of performances on Jimmy Fallon show were scrapped in 2014 following Bono's bike accident
Singer still can't bend two fingers
Alexander Starovoitov claims the band "spammed youths with illegal content"
The band's straight-to-iTunes release was available on vinyl
The band recorded early albums 'The Joshua Tree', 'Boy' and 'War' at the Windmill Lane studios
Band will play The O2 Arena on November 3
Band's 2014 album was automatically downloaded to all Apple subscribers' iTunes accounts
One of the tree's 'limbs' has been hacked off