Thanks for your thoughts on this, Thijs! Here's Tobias, the CEO of Tower.
We want to make sure that Tower can stay a high-quality application in the long run. This means we want to constantly improve the application, add new features, fix bugs, and help users with great customer support. To be able to do that, we need a steady and reliable source of income. The thruth is: for us - a small, self-funded business - a recurring revenue model from a subscription is the only sustainable way to survive.
A model where the user gets to keep the last version after she stops paying for the product does not work for a small business. If you have a team of 1,000 employees like JetBrains, you might be be able to afford this. But not a 7-person team like ours. For two reasons:
(1) First, it doesn't provide the steady and reliable source of income that we depend on. It's the old one-time payment model of the past - which we tried and which did not pay the bills for us in the long term.
(2) Second, and maybe more importantly: very quickly, there are lots of different old versions of the product out there. People want bugfixes, documentation and support for their version, no matter if they're currently paying or if they don't anymore. With a 7-person team, we simply cannot do this. We need to focus all of our painfully limited time on _one_ version and make sure to improve that one.
Most of our users make a simple calculation: "Can Tower help me or my team save some time or prevent some mistakes?" Over the course of the next 12 (!) months, even 1 or 2 hours or a mere handful of mistakes would make this worthwhile. If so, Tower has _easily_ paid itself off.
We offer a free and fully-featured 30-day trial that will help you answer this question for yourself - without any risks or commitments.
For the customer, automatically converting long subscriptions to perpetual licenses for an old version is a major safety net (the software will not stop working if I stop paying) and it proves that the vendor is committed to improving the product enough to make upgrades compelling.
On the other hand, reasonable customers do not expect support beyond the latest version and whatever they are currently paying for: "we have fixed that in the latest version, which you should buy" is a valid and honest answer to support issues.
For a tool that can be changed with very little friction like a revision control client, the typical "calculation" about spending money is likely to be waiting for an actual troublesome situation and then get out of it with a short subscription or a 30-day trial.
To summarise, you say you're not offering perpetual licenses for old paid-for versions because you don't feel you can make clear to your customers they don't come with support.
For some reason you do expect you can sell them on this new payment model that benefits mostly you, so it's really not your communicative skills or your customers' capacity to learn that are the problem here. That really only leaves us with the financial advantage to you.
Interactive Rebase (as well as Pull Requests) is already implemented! I suggest you check it out while it's still in Public Beta (= free) --> www.git-tower.com/public-beta-2018
No ETAs, but the team is fully and exclusively focused on making Tower better every day (meaning: no other projects). We're working on Tower full steam!
Our goal with Tower is to make working with Git easier and more productive, for both Pros and Beginners. We're putting a lot of time and effort into design, workflows, and usability.
Additionally, we're making a lot of Git's "power-features" more accessible: it's not enough to just "somehow provide" a feature like Interactive Rebase. It's only helpful when it's carefully designed and really useable...
With the current Beta version (www.git-tower.com/public-beta-2018), I think we've made great progress to achieve these ambitious goals. However, of course: please see for yourself :-)
Tobias here from the Tower team! I'd like to confirm your assumption: we're indeed working full-steam on improving Tower for Windows (and Mac, of course ;-)
We have quite some exciting features and additions on the roadmap!
Tower team member here :-) We are of course working on lots of improvements, especially in the current beta phase. Regarding interactive rebase, by the way, I can say that it's already on the wish list :-)
Tower team here: thanks for pointing this out! This is already on our todo list - and, in fact, already being worked on! Won't be an issue for very long ;-)
The learning platform on git-tower.com/learn also contains lots of content for learning Git on the command line (without Tower). This is true for both the 150-page book and the 24-part video series.
Thanks for reading - and for the time to write down your feedback! Much appreciated!