The author seems bothered by the multitude of negative reviews and support requests generated by a cheap app. Not all of these are bad - in fact they are real-world user tests and are useful for debugging and improving the app.
I propose having a free version for those who want to try out the app, with a caveat that users who need better support and more frequent upgrades should try out the paid app instead.
http://www.eurogamer.net/articles/2013-02-11-games-without-d...
(Though it only looks at xbox 360 games)
You could just as easily rewrite the conclusion to be "companies who knows their game is crap often choose to make a demo". Without a more sophisticated statistical analysis, it's every bit as valid.
Personally, if I play a game and see how its core game mechanics work then I am much less likely to purchase it.
A lot of my game purchases are impulsive — I see something cool in the trailer and want to try it. Once I've tried it I lose interest. Demos give me the opportunity to lose interest without purchasing the game.
When I know I really want to play a game all the way through I will always purchase it without trying the demo (if available). So in my limited gaming experience demos have never been a step to a sale.
Any number of things you could take into account.
You can see this in practice by watching MMOs after the first month many of them will lose tons of customers because now everyone knows the game is bad and not living to the hype.
Whereabouts you can see good ones such as WoW (or even Diablo 3) which will keep adding more users.
And the article also states that marketing budgets are not taken into account in the research. High-profile games are marketed more widely, and don't need demos, leading to the result that games without demos sell better.
When I am looking to download a new app, I can never tell from the description and screenshots if it's good or not, so the question is always - "What if it's crap". With an app that costs 0.99, the answer is simple - "Let's try it and see", so it's effectively a very cheap trial ... that just happens to come with a free full version. I would've readily paid more for latter, but I already got it and it was free, so what's not to like. This is why in-app upgrades would seem a natural way to convert people who like your app into paying customers. Let everyone kick the tires and let those who like it move on to a full version.
tl;dr - Indeed start charging more, but through in-app upgrades.