I've got an existing app that doesn't require any user sign up that allows users to organise lists (all on device storage). It has about 5000 users and I'm thinking of ways I can add value for my users and also make some money. I have an idea of some extra services I can offer as part of a premium subscription but I'm struggling a bit with how best to layout the signup flow (I'm a developer by trade).
The app uses data from another 3rd party tool, that although it offers an API where a users authenticates against, it's not an authentication system. Therefore I need to create my own registration flow as well so that I can manage the users IAP subscription against a specific account. One user in my system could potentially link multiple accounts from the 3rd party tool. So I can't just link the IAP to the 3rd party account they link.
My main question is really how to set-up my registration/subscription flow as it feels like there's multiple steps where a user could drop out if they're not aware of all the steps.
I believe that I first need them to register for my "app account" and then get them to sign up for the IAP subscription. Once they've subscribed they could then link their 3rd party accounts.
So in essence Register -> IAP Subscription -> Link 3rd Party account.
My initial thought is that this really comes down to a clear explanation of how to sign up for the premium offering and what it's offering on any potential signup page?
I did think I could go with the subscription signup first, but then I wouldn't be able to link the subscription to a specific account in my user system.
Does anyone have any thoughts or advice on how best to set-up this flow?
I did have one thought about creating a separate "Premium" version of the app but it might then be more difficult to get this premium offering in front of existing users.
Would really appreciate any thoughts.