People complain that Nirvana, Nozbe, and Todoist are subscription based. They want free apps that sell their profiles to advertisers or "No SaaS. Pay once, use forever" like Everdo which is not a sustainable business model. One should not believe in apps paid once and then updated eternally... Just saying. @MateuszNo, I have not. But since I use Nirvana, I don't see any reason to switch based on what I see on their website.