@swehba, Scapple for Mac is coded by Keith, who is the sole Mac and iOS programmer; as such, for the last few years his focus has been on major developments for Scrivener 3 as well bringing the code in line with new Apple frameworks, and, having had to take over the programming of the imminent Scrivener for iOS project, for the last year has had to concentrate on bringing that to fruition. In that scenario, Scapple has inevitably been put on the back burner. He will be aware of requests that have been made, and no doubt, when the time is available, he will put his mind, time and energy to those he thinks have merit.
@skyriani, I am sure that Keith is fully aware of how many people would love an iPad version, and my betting is that Keith sees the merit of an iPad version, but, given the above, I wouldn’t predict its appearance any time soon, as that would be yet another new project. (On the other hand, who knows, maybe he has been tinkering away at it in the small hours of the morning as a relief from his 14 hour days on Scrivener programming! )
As for the Windows version, LAP and Tiho_D must be fully involved with working on Scrivener 3 for Windows, bringing it up to parity with the Mac version, and at the same time rewriting the code as necessary in the newer version of Qt. They too are unlikely to have time or energy for Scapple until Scrivener 3 is out.
All that said, Lit&Lat, has always made clear on their website that, while being open to suggestions and comments, you should buy their software for what it can do, not for what you would like or hope it could do at some point. They give very generous trial periods precisely so that people can thoroughly road test their software to see if it meets their requirements or not before purchasing.
Mark
Just a user of Scrivener, and although I have Scapple, I have not yet found a compelling use for it.