The more I’ve been accumulating apps on my iPhone and iPad over the years, and the more I had to perform periodical cleaning up to avoid filling up my devices, the less I’ve been prone to impulse purchases. It’s really not a matter of price: I have insta-bought relatively ‘expensive’ apps, such as Paper by Fifty-Three (with all its in-app purchases), without a problem. It’s simply a matter of clutter and value: looking back on past impulse purchases, I noticed that in many cases, after the initial novelty rush, I stopped using or caring about an app altogether, and in some cases the app’s ‘screen life’ in my iPad or iPhone’s springboard has been quite short.

Yet I monitor the App Store constantly, and I’ve been doing it for a long time using AppShopper (the older, non-social version). Again, it’s not (entirely) a matter of price. Sure, AppShopper is great to keep tabs on an app wishlist and to be alerted when apps of interest drop in price. The truth is that I find AppShopper’s interface a better option than using the built-in Wishlist feature in Apple’s App Store app.

Over time, I’ve noticed certain marketing tactics on iOS developers’ part, and there are two cases in particular that I, as a customer, just can’t tolerate. 

1. Apps requiring their In-app purchases because they’re plain useless in their basic version — There are apps that, on paper, come with an impressive set of features. Too bad that you have to buy every — single — little — one of them, even very basic ones, otherwise you won’t do much with the app. I won’t make specific examples, but imagine a photography app that features single editing tools, like Crop or the Saturation slider, as In-app purchases. Dear developer, you may have tricked me into downloading your ‘free’ app, but rest assured that once I discover your questionable In-app purchase tactics, I will delete your app right away.
2. Maddening, bewilderingly frequent app price fluctuations — This is the most baffling and infuriating practice I’ve ever seen in the iOS App Store, something I noticed thanks again to AppShopper’s App Activity section. It works like this: 
   • App is released — Launch price! $0.99
   • Two days later — Price increase: $2.99
   • One day later — Price drop: back to $0.99.

   It doesn’t matter how beautiful or useful your app can be. You change your prices like this and I guarantee you that — on principle — I’ll never buy your app or apps. Ever.

Jonathon Duerig on App.net said it best:

The biggest aggravation to customers is the feeling of being a sucker. And lower launch prices both discourage later purchase because it will seem overpriced, and loses revenue from your biggest sales spike.

As a customer who doesn’t mind paying higher prices for well-designed, useful and thoughtful apps, my suggestions are simple: 

• First, if you offer in-app purchases, find a reasonable balance between the basic functionality of your app, and what the various in-app purchases will provide. I find ‘packs’ to be a very nice in-app purchase format: additions that come in sets (like filters, themes, instruments, sound effects, etc.). In this case, the app should work with a ‘base set’ well enough, and additional sets soon become great ‘really nice to have’ building blocks. But if your app is just an empty container for in-app purchases, then I’m sorry but I’ll look elsewhere.
• By all means, do promotional launch price discounts, then increase the price and have the courage to stick to what you think your app is worth. From then on, the occasional price drop is welcome, but make it meaningful (it’s a special anniversary, or you’re about to launch the all-new and improved separate Version 2 of your app, or you don’t plan to support the app anymore, that sort of thing). Avoid giving customers the impression that it’s something completely arbitrary. That’s disrespectful.