Reps is a single purchase. There is no subscription, no in-app purchase, no premium tier and no free version waiting to nag you into an upgrade. You buy it and you have it.
The purchase is a Universal Purchase, which means one payment covers iPhone, iPad and Mac on the same Apple Account. Buy it on a phone and it is already there when you install it on a Mac.
Reps also supports Family Sharing, so one purchase covers everyone in your family group. Each person gets their own separate library on their own Apple Account, which is the arrangement siblings actually need.
A subscription makes sense for software with running costs. A service with servers to pay for, storage to maintain, and staff answering support has an ongoing bill and it is reasonable to ask users to share it.
Reps has none of that. There is no server, no account system and no infrastructure sitting behind your cards. Nothing is being spent on your behalf every month, so there is nothing to charge for every month.
A student is on the hook for a lot of subscriptions already. A four-year programme turns a modest monthly fee into a significant number, and the material you built is usually held hostage to it: stop paying and your own cards become read-only or disappear.
Your Reps library is a set of files in your own iCloud account. It does not stop working.
No ads, no sponsored decks, no upsells inside a review session. Nothing in the app is trying to sell you something while you study.
None at all.
No. There is no free tier and no time-limited trial.
No. A Universal Purchase covers iPhone, iPad and Mac on the same Apple Account.
Family Sharing covers your family group with a single purchase. Everyone gets their own library.
No. Updates are included.