When you beat the entire first world it automatically unlocks the other two.
Current: HTC One (Stock, Rooted, Unlocked, S-OFF HBOOT 1.56, Tampered flag removed)
Backup: Samsung Captivate (CyanogenMod 11 Nightly)
Tablet: Nexus 7 (Rooted, TWRP Recovery (I think)) Android 4.4.2
Defunct: Samsung Galaxy S2 AT&T (CyanogenMod 11 Unofficial)
Thank god for having spare cell phones and custom roms that make them survive for a bit longer.