There is a subscription. There is also a door out of it, and that door only exists because of a technical decision made early on.
They get treated as one, but a subscription is usually the honest answer to a recurring cost. If an app streams you audio, stores your files, or sends every request off to a machine that costs money to keep running, then serving you in March costs roughly what it cost in February. A monthly price matches a monthly cost.
Building and supporting software full-time also costs something every month, and pretending otherwise is how small apps quietly die. So yes, there is a subscription here.
Aloud generates its narration on your iPhone. The voice model sits on the phone, the synthesis happens on the phone, and the audio never leaves it. Every hour of listening you do costs the studio exactly nothing, because it runs on hardware you already own.
Once that is true, the usual argument for renting stops applying. There is no per-user bill arriving every month that a monthly fee has to cover. So Aloud also has a one-time price: pay once, keep it, nothing renews.
Most audiobook apps cannot offer the second option at any price, because their business is selling you audio from their servers. Ours is not.
If you buy Aloud outright, it keeps working when the studio does not. No server switches off, no licence check fails, no library evaporates. Your books still read themselves to you on a phone with the wifi turned off.
That seems like the right property for something you paid for, and it is the reason the on-device constraint is worth the trouble it causes everywhere else.