The problem is you then have to have two versions in the App Store, Acme and Acme Pro. Each version will have to go through the torture that is the App Review process. What if one gets rejected, and the other doesn't? It's a pain to have to start over again and lose another week, not to mention coordinating marketing, etc.*
If you decide to sell the Pro features as an in-app purchase, i.e. pay $9.99 for "Pro", what happens next year? "Pro 2014", "Pro 2015" ... ? Also this assumes that your app is built such that Pro features can be isolated from the rest of the app.
*EDIT: Also, if you have a free app and a Pro app, and the user finally decides to purchase the Pro app, with sandboxing, you now have a problem of how to best migrate user data to the Pro app.
"The problem is you then have to have two versions in the App Store, Acme and Acme Pro. Each version will have to go through the torture that is the App Review process. What if one gets rejected, and the other doesn't? It's a pain to have to start over again and lose another week, not to mention coordinating marketing, etc."
Exactly, which is why I said that Apple needs to allow for trial versioning. Otherwise, people attempting a freemium model are forced into this inelegant and suboptimal execution of freemium.
The problem is you then have to have two versions in the App Store, Acme and Acme Pro. Each version will have to go through the torture that is the App Review process. What if one gets rejected, and the other doesn't? It's a pain to have to start over again and lose another week, not to mention coordinating marketing, etc.*
If you decide to sell the Pro features as an in-app purchase, i.e. pay $9.99 for "Pro", what happens next year? "Pro 2014", "Pro 2015" ... ? Also this assumes that your app is built such that Pro features can be isolated from the rest of the app.
*EDIT: Also, if you have a free app and a Pro app, and the user finally decides to purchase the Pro app, with sandboxing, you now have a problem of how to best migrate user data to the Pro app.