Re: How much for iPhones
Depending on what you want to do to the users, it is almost certainly possible, but it's not a one-to-one comparison with the thing discussed in this article.
This article is mostly discussing embedding malware into an app which will install itself as another app. In that particular case, it actually isn't possible on unjailbroken IOS because Apple really hates the idea of anything installing an app which isn't them. Even on Android, the user is going to have to be tricked into undoing a security feature in order to allow this, and possibly two if they don't have the general "install apps from untrusted sources" switch turned off yet.
However, you can always put a malicious app directly into the IOS app store. You need to be careful that Apple's automated analysis doesn't flag it, so probably put up a benign one first and introduce the malicious behavior later. That most certainly can be done. You can also put in an app which will retrieve and execute scripts from an external location, then manipulate those to produce malicious behavior. I'm sure you can buy something like that, but it's probably more restricted because it's going to require custom work to port malware to such a system whereas your Android malware can be a normal app.