How Apple and app developers will try to entice you to subscribe, not just pay once
From Ars Technica:
Apple continues to refine subscriptions for devs in hopes they'll adopt the model.
For a while now, Apple has been encouraging app developers
to consider subscriptions as a key revenue source, and the company is
introducing some new options for developers that it hopes will make the
option more attractive. In the past few days, Apple has informed
developers that they will now be able to target current and recent
subscribers with promotional rates on subscriptions. That means
developers will be able to offer discounts to try to get you back if you
lapse, or they might try to entice you to stay if you're considering
leaving.
Developers could previously offer limited-time subscription discounts
but only to new users. The new model is available in recent beta
releases of iOS 12.2, macOS Mojave 10.14.4, and tvOS 12.2, and it is
likely to be included in the final public release for each. Apple will
facilitate three different types of offer for developers who want to
retain or regain subscribers.
Here's how they're described in Apple's App Store Connect post on the subject:
Free
Customers access your subscription for free for a specific duration—for
example, a 30-day trial for a subscription with a standard renewal price
of $4.99 per month.
Pay As You Go
Customers pay a promotional price for each billing period for a selected
duration—for example, $1.99 per month for three months for a
subscription with a standard renewal price of $9.99 per month.
Pay Up Front
Customers pay a one-time promotional price for a specific duration—for
example, $9.99 for the first six months of a subscription with a
standard renewal price of $39.99 per year.
To deploy these offers, developers will need to implement new StoreKit
APIs using the latest beta version of Xcode. They can test using the
aforementioned iOS, macOS, and tvOS betas, but the offers will not
become available to users until the "the feature is publicly available."...MORE