Blair Hanley Frank at Geekwire.com asked some excellent questions for the article about our upgrade scheme, Pete, Shawn & I worked together on some answers... I'm better at writing code, but they're better at writing words!
1. It seems like your method creates a number of apps with similar names and the same functionality. Are you concerned about fragmenting your user base?
There is no system in place to do anything other than to fragment. If a developer wants to charge a different price for their app for iPhone and iPad the only way to do that is to release two versions which fragments the user base. There's no way to set version 4.0 as a paid upgrade with the option to tell your users ahead of time or give them the option not to upgrade if they don't want to pay again. Removing the older version from the App Store cuts off your existing user base and prevents any bug fixes.It would be so much better if Apple did this so all the app variations (iPhone, iPad, iOS6, iOS7, free upgrade, paid upgrade) aren't needed. Once the iOS7 versions are going, we may do some changes to the keywords for the earlier versions so they aren't very easy to find, and we've already added descriptions to go get the iOS7 version.
So while we are worried about fragmenting our user base, there is no alternative way of doing the things we want to do.
The need to maintain a sustainable business--and free upgrades forever is not sustainable--had to override our concerns with fragmenting the user base or releasing multiple variations of one core app. Ongoing development of an app or any piece of software takes time and money. If an app isn't going to be a 1-off 'disposable' piece of software then developers (ourselves and everyone else) need the resources to keep going. Any app that ceases to be profitable will cease to be worked on. Whether that means the developer abandons the app and moves on to the next thing or goes of business entirely. And if that happens then there won't be any more fixes or improvements ever.
2. I know that apps that are free with an in-app purchase to upgrade to the full version have occasionally garnered a significant number of one-star reviews because users thought they were getting the full app for free. How concerned about that are you?
I'm sure we'll get a few 1star reviews, but over the years, people have become more accustomed to free apps having things to upgrade, so hopefully not too many. A note about the purchase required is the first part of the app's description in the App Store, so we are trying to be as up front as we can be.
Our FTP apps are more specialized tools, so even people seeing it for free wouldn't pick it up the same way they would a game.
3. I know you noted in your post that you think this method has a greater chance of long-term success than the program that the Omni Group tried for their App Store upgrades, but are you at all concerned that Apple could still pull the plug on what you're doing?
Omni Group's system let you get upgrades from their website of an app you had purchased from the Mac App Store. I believe getting something anywhere outside the App Store for something you'd purchased within the App Store was the problem. Our way is all within the App Store, so as far as I can tell from reading all the information, that is OK. We were as explicit about what it does in the review notes to Apple as we could be, even saying we hoped for a higher level review to make sure it is allowed.
We are absolutely concerned that Apple could pull the plug. And if they do, we will revert to what Omni Group did for their iOS7 updates--release new apps for iOS7 and charge full price. We were and are willing to take the risk and be kind of a test-case because we believe that this is a necessary evolution of the AppStore if business tools, utilities and other long-term and non-disposable apps are to remain viable.
Let's say a developer writes a great app and sells 1 million copies then works for a year on version-2. If version-2 is released as a free upgrade then the 1 million people most-likely-to-buy-it end up getting it for free. The developer gets a lot of happy customers, but no financial compensation for all the hard work. That needs to change. If version 2 is released as a new app, even if only a fraction of those million people will buy it, the developer comes out ahead.