If you're an iOS user, you're no doubt unhappy that Amazon made Comixology pull in-app purchases on your platform of choice. However, the service is offering a nice consolation prize: it's giving away 20 free comics over 20 days, regardless of what technology you're using. You only need to "buy" a freebie within 24 hours to add it to your collection. You'll have already missed out on the first offer as we write this (sorry!), but there's 19 more to be had through June 14th -- that should be enough reading to keep you busy on your big vacation.