When they have you pretty much locked in, they have no reason to remedy, rectify, or innovate.
SAAS that stops working fully when you stop paying is a terrible model for users.
I think it can go both ways.
I’ve seen developers and publishers abuse the upgrade model; holding simple features and bug fixes to ransom for exorbitant upgrade prices.
I’ve also seen many promising small apps stagnate and become discontinued or abandoned because the developer has no means or motivation to keep it going (iOS especially).
On the other hand I’ve seen big, well established brands transition to SAAS when they don’t really need to purely as a money grab. Very often these big established products like Adobe CS have had the features required by most users for years, so because users don’t need or want feature updates and improvements as much as the developer would like, SAAS is a way to force them to pay for ongoing maintenance and development.
I’ve always been of the opinion that bug fixes and security patches should be free for end users, but again bigger players don’t tend to see it that way.
So personally I don’t tend to mind SAAS for smaller, cheaper apps (< $50/year) that I use frequently, show promise and which I’d like to support, but I still shun it for major applications where I’d like to decide whether new versions and ongoing development are worth paying for.
As for this app in particular I hadn’t really heard of it but apps like this are a dime a dozen at the moment. Developers really need to do something special to compete in this genre. I couldn’t see anything this app does that at least half a dozen I can think of off the top of my head can’t.
Personally, I can’t go past latex because it produces by far the most professionally typeset results. Only problem is its learning curve and that most people outside of academic environments won’t touch it.