I am making a web based multiplayer game in HTML5 (plus some python code for some server side stuff). My original plan was to try and monetize this via a freemium model (with realistic expectations..). I am intending to use phonegap to package the HTML5 into webapps for the iOS, Google Play and Windows mobile stores, as well as hooking into the facebook game API. All of this is in addition to accessing the game via a browser on any device straight to the main website of the game. I planned to make the 'app' freely available from app stores, with the in game purchases handled (somehow) seperately from any single app store, since the app is just an interface to a game that exists outside of the app and players may well be playing from multiple devices all accessing their same player account.
It occured to me though that the various app stores might frown on this and I don't want to jepordise the chances of the app being accepted. On the other hand, it makes no sense for someone to purchase something in game through their iPhone, but not have access to that when they login to the game via their Android tablet, or web browsers on their home PC. The same goes in reverse, if they buy something directly through the website from their home PC, they should have access to it through their iPhone.
This issue must have been encountered before with many other games, so what are the ground rules? Note that I'm not trying to get around the app store commissions, I'm just trying to ensure players can access the game smoothly and consistantly through multiple devices.
Note that since it is in HTML5 (and doesn't use any native app APIs like the accelerometer, geolocation or camera), I could simple do away with the app stores and simply have mobile players go straight to the game URL via their browser and their game experience would be the same. The only reason to use phonegap to convert to something that can be packaged through the app stores is for marketing purposes.
To give some further detail of the freemium model (in case that makes a difference to the answer), I am planning that the in game purchases are not in game commodities as such, but rather the unlocking of features. Free version players will have basic features, then I'm planning on two tiers of extra features that can be bought for limited time. The reason for this is to give players the confidence that while paid version players have an advantage, the advantage is fixed rather than having an infinite ability to simply buy more and more stuff. To my mind, in the context of this game, this would make people more likely to pay as they know paying that small amount is enough to ensure they will be at the same level of advantage as other paid players. To be extra clear, this is a sports management/simulation game. The extra features are things like better training facilities etc.
I'm sure this question, or something similar, must have been asked before but I couldn't find anything using the search function. Maybe I missed an important keyword.