This is a general question about the Bus factor (Bus factor - Wikipedia) and how long the app will keep working if @tolriq has an accident.
Is there a backup person that will/can takeover the project?
How long will the license validation work?
Are these private server that do the validation or is it a google playstore server? (If the private servers don’t get payed they will go away with probably all the logs which person owns a license)
I know that without updates some media provider will stop working because of api changes etc. is there maybe a plan to open source it? (If there is no new “owner” of the project)
I ask this question with the same mindset of having a backup.
Hopefully never needed but in case if happens it is clear what to do.
There will probably be WWIII before I can also just stop everything at any time As any application you purchase.
It’s funny how people on phones expect apps to be continuously updated for a single time payment of less than a coffee and see absolutely no problem with that.
I understand your frustration and don’t expect this.
My main point is that if i purchases a program i would like to be able to use it forever even without updates. (I still use Microsoft Office 2016 and am happy without updates)
As described in other messages about the true “offline” capabilities of symfonium it tries to validate the license in increasing timespans.
→ Symphonium won’t work if the license can’t be checked.
I asked this question because another company killed their “Lifetime” purchases Red Sky Labs Muzio Player Premium post-purchase terms change (video) and there are a lot of companies that take there licensing server offline (Often after they changed their model to Subscription and realistically no one is going to sue over a cup of coffee and in the user agreement you most certainly agreed that you have a revocable license that can be revoked for any reason they want)
In the video 1:10 Louis Rossmann also mentions how he understands that it is unrealistic to expect a lifetime license and regular updates i support this fully and am happy you are doing this at the moment.
Ideas for you:
You could split your app in multiple versions “Symfonium v1”; “Symfonium v2”; … (I guess this would kill your discovery)
Hide new versions behind an if statement. The user always purchases the current version but doesn’t get the new major versions for free. If there is an api change in a media provider or android itself the user would simply need to purchase the next version if it is fixed in it. Drawbacks: People will complain and increased Support as bugs that got fixed are not accessible for user with an old license and the fix for them is to buy the latest major version (You could limit Support to the latest major version). Another problem is that your code will get messy as you will not remove old code only add new one. (That is like a soft subscription but i think a lot of people would be understanding of this solution)
edit: You even cover this in your FAQ (“lifetime access to current features”)
edit2: I don’t mean to say you are going to do change to a subscription model but if the license server is no longer online it doesn’t matter what the reason for it is.
Just a thought: an accident may be way less likely to end the app (or apps or software in general) than economic viability. So as long as we buy, donate, contribute to this app, it might be kept alive by the man. Not being against open source in any way, but I have the feeling that is the major reason for the end of many small projects: developers get new priorities in life and have to prefer those that secure their economic survival.
This intent might contribute to that - not in the case of Microsoft, but for many smaller developers who are dependent on a way smaller stream of income. If everyone only buys once in their lifetime, it means that the dev will get one meal (or one coffee, or even less) out of every single app purchase. Try to calculate from that how many sales you would have to make to secure a stable support for yourself and your family at least for a couple of years.
Another misconception here is the word “lifetime”. It is not about your lifetime.
Yes and no. Back when software was sold with “perpetual licenses” it was typically much more expensive. Adobe suite used to cost upwards of $1000 and typically you’d buy a newer version for a slightly cheaper (or even full price if you skipped a version) every couple of years. But your old version would still continue to work just fine without new features. I would argue that this was better and more sustainable for developers.
Now we live in a world where (largely) Apple has set the expectation for software to cost no more than a cup of coffee. This also increases the need for DRM and online activation / verification of licenses. When you’re only getting a few bucks from each customer, you need to make sure you are actually getting those few bucks from each customer. Yes, adobe had license activation way back when, but it wasn’t nearly the hit to their wallet when some poor high school or college kid pirated their cracked software without paying, as most of their revenue came from businesses purchasing licenses.
What’s worse, is that there’s now a middleman or gatekeeper taking upwards of 30% of each purchase right out of the developers pocket. I don’t believe it’s accurate to say that the customers expectation of being able to use the software they purchased in perpetuity that is making it difficult or unsustainable for developers. Its the market conditions created by platform operators that developers are forced to exist within. I think it’s perfectly reasonable to expect that I be able to continue using something that I purchased as long as I like.
That doesn’t necessarily mean that I expect free updates forever. But being able to use something as is, makes sense.
Dealing with these market conditions is why so many things have gone to the subscription model (as a small developer anyway; adobe is just squeezing more profit… They don’t need the subscription model to be able to feed themselves).
Blackberry apps were regularly $20 or more, and nowhere near the quality of modern apps, but if a developer tried to charge that much today, they’d be review bombed with 1 star reviews into oblivion. I, however, being a reasonable adult, would be more than willing to pay $25, $30, probably even $50 for Symfonium (and I plan to continue donating as I have spare cash to do so) because I get at least that much value from it, and it’s more than obvious the amount of time and effort that has gone into developing it. The $5 or $7 that it costs is more than a bargin. It’s pretty awful that developers aren’t able to ask what they’re worth I’m todays market, and that’s is absolutely not the fault of the consumer.
Its no different than having a career in a trade where you’re typically earning $100k or more a year and them suddenly the state decides to no longer require the education and licensing that you had to invest in to do your work, causing the market to be flooded by any amature with a screwdriver, causing your wages to fall to that of an entry level nose picker taking home $35k/year before taxes. That’s market conditions being changed, just the same, and not the fault of the consumer who’s happy to save 50% on the cost of labor.
I can also just stop everything at any time 
As any application you purchase.