Full price upgrades works for Angry Birds, but anything less episodic or standalone and you have problems. See Tweetie 2, for an example.
This issue is going to be rampant in the Mac App Store very very soon. It's been out for what, a year now? Time for a round of big updates... now you have two copies of all your apps.
What's the example, exactly? Genuinely curious. I upgraded to Tweetie 2 as soon as it came out. My impression was that it was very successful right up until Twitter bought Atebits.
It's hard to say how much of that was noise, and what effect it had on sales / success, but there was a lot of hype about the paid upgrade leaving people unhappy.
Example headlines (Google "tweetie 2 paid update" for more):
"Tweetie 2 Pricing Controversy: An Interview with Tweetie's Creator ..."
"Tweetie 2: 'New App' – Will Spit On Existing 'Old App' Users | iSource"
"Still won't pay for Tweetie 2 upgrade? Try these Twitter apps ..."
"Tweetie pricing fuss highlights App Store flaw | Macworld"
Fair enough. I'm not sure a mechanism for having paid upgrades under the same name as the original app would have avoided any of those headlines, though.
You don't? If people had complained about being charged a reasonable, discounted upgrade price for Tweetie 2, they'd have been laughed at. That has been a common model for software upgrades for as long as I remember (and quite probably longer than I have been alive).
People always complain about being asked to pay to upgrade. If they don't get a discount, they complain about that. If they do get a discount, they complain that the upgrade "should have" been a free minor version bump instead.
In my experience, at least, it's more or less just a pathological behaviour that you can't escape.
Angry Birds and other games are in a totally different category. If you buy “Angry Birds Space” it’s reasonable to assume (a) you’re done with the original, and (b) you’re going to get as many hours of enjoyment out of it as the original, so it’s fair to pay as much.
This isn’t the case with productivity applications, necessarily – you can keep using Delicious Library 2 and it’ll keep working great, so we need a way to reward customers who say, “Yes, I’ll pay to have some extra functionality.”
