IAP in general is fine, but a lot of these apps are bait-and-switch. They do not make it clear up-front that unlocking critical features requires payment. Games are the worst. There are so many "free" games which simply do not allow you to have fun without spending money. They claim to be free, but then it turns out you have to grind pointlessly unless you pony up the cash. It's gotten to the point where I won't bother with any free app that's listed as having IAPs.
I much prefer the "Lite" model, where you basically have a functional demo for free, then a separate paid app. Offer the paid features in the "Lite" version as an IAP too, if you think that helps.
What it comes down to is that a good transaction should be a net gain for both sides. I give you money, and in exchange I get something that's worth more to me than the money I give you. We both win! But the way many of these games are done, the creator deliberately makes their game less fun in order to make it more lucrative. It's no longer mutually beneficial. Rather than adding value to get more money from me, they actually reduce value to try to extract more cash.
I much prefer the "Lite" model, where you basically have a functional demo for free, then a separate paid app. Offer the paid features in the "Lite" version as an IAP too, if you think that helps.
What it comes down to is that a good transaction should be a net gain for both sides. I give you money, and in exchange I get something that's worth more to me than the money I give you. We both win! But the way many of these games are done, the creator deliberately makes their game less fun in order to make it more lucrative. It's no longer mutually beneficial. Rather than adding value to get more money from me, they actually reduce value to try to extract more cash.