Software used to be something you bought. Then it became something you rent. The rent never stops. The features rarely keep pace.
SixTwelve does not rent software. Every app on this site has one price. A camera is $4.99. A PDF workbench is $9.99. You pay once and it is yours.
What you do not get
No account. No sign-in screen before you can take a photo. No analytics SDK counting your taps. No push asking you to rate the app on day two. The camera opens and it is a camera.
Why it works for a small studio
Subscriptions exist to smooth revenue for companies that carry large payrolls and investors. This studio carries neither. It builds small, single-purpose instruments and sells them to people who want them. That is the whole model.
It also forces discipline. If an app has to earn its price once, it has to be finished on day one. It cannot ship half-built and promise the rest behind a paywall.
Where to start
If you shoot on an iPhone, start with the camera shelf. If you live on a Mac, look at the Mac tools. Linux users have their own shelf, and several of those tools are free.
Pay once. Keep it.