Nate Boateng has published a very good explanation of why App Store users aren't entitled to free, universal upgrades of iOS apps:
The thought that a small development team is expected to do months work for free is insane to me. Yes, there are tons of successful apps that are universal (see Instapaper, Due, and Twitteriffic), but the perception that we are entitled to that is not only selfish, it’s just plain wrong. Universal app updates that come for free should be considered a bonus, not a right. A while back Iconfactory developer Craig Hockenberry gave a ballpark on Twitteriffic’s development. He estimated that it cost around $250,000 to develop Twitterrific. Think about that for a second. Still think you’re entitled to free universal updates for the lifetime of an app? I sure don’t.
Today's Tweetbot releases are just another example of a subset of users that think developers should keep on updating their apps, even adding completely new iPad versions, for free, forever. This kind of controversy seems to take place every time a major iPhone app is released as standalone on the iPad, or vice versa. So I'd like to formulate a quick thought on the subject.
I understand those who say "I would have preferred it to be universal". Sure, sounds reasonable. I would have preferred my iPhone 4S to come for free in the mail, too, but it didn't. Stuff isn't free in this world (even when they give you the illusion of free, you're the one being sold). What I can't accept is people getting angry and offensive at third-party developers that decide, you know, to make people pay three bucks for an app that's been in the works for months. Unfortunately, the App Store doesn't allow for paid upgrades, so if these people's rhetoric is that it's not about the price, it's about the convenience of a universal binary, well, there isn't much developers can do about it. Ask Apple.
More importantly, I'm baffled when I see people really getting angry because of a standalone app that was always meant to be that way. So here's a tip for these people: next time you're about to send a tweet to a developer, claiming that he promised a free and universal update and he's now "stealing your money", do your homework. Because if I can't argue on economics, I sure think I'm pretty good at Google Search, which brought me to this page (screenshot). From the old Tweetbot FAQ, when the iPhone app was first released in 2011:
Will there be an iPad/Mac version?
It’s a possibility, but we have no plans for it at this time. We are focusing on the iPhone version for now. If we do an iPad version, it will not be universal.
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