Wynapp
I have 2 years of experience of cross-platform development in different domains (tourism, smart city, utility), 4 years of native Android, and 15 years of software engineering career (distributed systems, web apps and portals, web services). References to the existing apps may be provided upon request.
As for the coupons, the solution may depend on the distribution model (see my question below). However, a possibility may be to have a possibility in the app to "unlock" the free trial entering the coupon code. The code may be verified locally or remotely (recommended for better security, but far more complicated) and in case of positive answer, the functionality is unblocked.
I would kindly ask you for some details (if you intend to award me a bid):
- do you want to publish two apps in the market (free trial and full version) or have a single app that requires the user to pay after one week?
- as far as I understand, the app data is managed completely locally? No backend synchronization is required? Should it provide any form of backup for data?