Free download for the plugin during development is here for any and all:
Jeff - Use Cases - Here are some that come to mind:
Public well known app known as myFitnessPal - they have a yearly and a Monthly Subscription to their content. Well known fitness App - about $45 yearly and $7 monthly.
Financial Application where you are charging access to financial data - There are too many to mention - I've worked on several - you can find them on the App store.
Garmin - has a their GPS app. You can pay $1.00 a month to subscribe to their 'traffic' service.
I have a Client in Australia - they have an app that provides proprietary access to data about the availability of health care services from the government - they charge a monthly flat rate subscription to their app.
Health Care App for Care Providers - Monthly Subscription to use the App that provides to sharing of data amoungst family members about a person under care.
Texting and Email Application - Subscription monthly for access to texting services which are an 'add on'.
Application that provides information to farmers about calves they are raising - annual subscription to an app that replaces 'manual data entry' ...
The use cases are by far to large to mention. I think that - from my perspective - subscriptions to electronic services have replaced 'buying' an app across the board - but - I'm sure that differs. I actually have subscribed to more valuable services - than - apps that I have bought in the last year.