Could you describe the user experience you have in mind? For example, if the "stickers" are for a pre-defined set of challenges in the application, and those challenges are accomplished in the application, that would effectively be an "achievement" system. In that case, you could potentially put the information on what the challenges are in Title Data, check for the player (or character) having accomplished them in Cloud Script, and award your "stickers". Alternately, a more direct way to do this would be to set up Segments in PlayStream which have as their definition the requirements for the challenge, and their Segment Enter Actions would then be the awarding of items, etc.
I want to create application for sticker challenge in which one can select the character and customize it by applying some powers on it and send it to the another. Next user can also view this character and customize it in his own way and send back and so on. So my questions are as:
1. How can I store the character data?
2. How can I store customized character data at user level?
It really depends upon the rest of the requirements, like how large the data for the character can grow, whether the character can have its own inventory, statistics, and virtual currency balances, how you want to share the character, etc. If you don't need distinct inventory, stats, and VC, you should just store the info about the character as player data or shared group data and send the info on the ID for it to the other player, so that he or she can modify that data.
