When it comes to certain apps or games, whether they be free or not, sometimes it can be hard to get around one simple fact about them that you're reminded of every single time that you open them up. That they contain IAP's or ads. Perhaps both. The inclusion of these two things don't necessarily make whatever apps or games that they inhabit instant failures or terrible apps. They do however both tend to come with a general negative stigma and therefore most people have a huge distaste for them. While ad business is pretty big business, In-App-Purchases is something that has become quite prominent over the last few years as well and you can pretty much see them in most games, and at least some applications. The thing with IAPs is that most people are weary of them, simply because they think that they may end up having to pay to progress. While this is sometimes true, it is not always the case and more times than not the IAPs are simply there for a convenience factor or for something aesthetic that is not experience impacting.
IAPs may not be everyone's favorite but they can sometimes be a little easier to deal with. They're integrated into the game or app so they are part of the UI, making them easy to overlook. Ads however can be anything from a full page size ad when you open an app or game, to the banner ads placed at the bottom or tops of screens while you use or play the apps and games that contain them. Then there are some ads that pop up right in the middle of whatever you're doing, and I like to think of those as the worst offenders. The last thing I want when I'm playing a game I actually enjoy is to have a giant ad manifest itself in the middle of my display, effectively cutting off any gameplay that I was engaging in. Sometimes it kills my desire to play that game altogether and I move onto something else. The banner ads aren't so bad because, while constantly there, they're usually out of the way and they don't impede your gameplay or app use unless you tap on them. Both ads and the In-App-Purchases are ways to monetize the apps and games that get used on a daily basis, and they're a necessary evil in some if not many situations.
People refuse to buy apps or games and so the developers need to look for another way to monetize their offering so they can get some credit and pay for their hard work. IAP's and ads are their two most profitable choices and both can be implemented rather elegantly, so long as they're not intrusive to the point that you want to immediately uninstall the app. At least with IAP's though you have the choice in many cases to deal with them or not to deal with them. I Play a couple of games pretty frequently at current that have IAP's within and I simply just ignore them. Doing so doesn't effect my gameplay experience and life goes on, as I continue to enjoy playing where others might find them useful and spend some of that real world cash. We both had the options to buy them or not which was great. The downside with some ads is that they can take over your entire screen, or just the most important portion of it. So while the apps or games that have those kinds of ads may not have any IAP's in them, the ads arguably cause more of an annoyance and they also impact the way you use them, just like pay to win or pay to progress type games. Neither are particularly enojyable to the point that we crave having them in our existence, but IAP's definitely feel like they can be ignored more often than ads. They feel like the lesser of two evils.