Inviting players to Game Center via email - objective-c

I am developing a Turn-Based Game Center game and wonder if it is possible to invite players via email and not only players that all ready have the game and a user-id # Game Center?

Turn-based games powered by GameKit require Apple-ID centric invites. You can't programmatically invite a friend, which you would need to do if you were sending out email invites.
If you want to do email-based invites, you'll have to code your own solution and only use Game Center for things like achievements and leaderboards.

To invite a player to an online multiplayer game using Game Center, the user must have a registered Apple ID. The user must also own the game to be able to accept, however I believe the user will still receive a notification in Game Center about the invite.

Related

Bubble notifications in custom app for Microsoft teams

I am working on developing an app for MS Teams. I want the app to send in-app/bubble notifications to user, to engage the user and draw his/her attention on action item. Could someone please guide how can I make that possible? I am unable to locate documentation for it. I don't want to send messages/ cards in channels via bot.
By "in-app notifications" I mean bubble notification kind of thing which conveys number of messages that are unread in "Chat"/ number of activities under "Bell" icon (currently available in Teams)

Household API not returning my household on my friends phone

I'd like to write an app that lets friends, who visit my place, control my devices using the Sonos API.
My friend is connected to my Sonos home (connect to the same wifi, open Sonos app, select "Connect to an existing system").
The household API only returns my friend's existing household, but not mine. This means that he can't query the groups or perform any playback/start/pause operation using the Sonos API.
Is there any way my friend would be able to control my devices using the Sonos APIs?
Thanks!
When a user authorizes an app to access their Sonos account, only that user's household(s) are visible to that app. The fact that the user is on another Sonos owner's LAN is not relevant, as all communication goes through the cloud.
The only way for user A to access user B's household is for user B to login to user A's app themselves.

Getting a users complete achievement list through Google+ API

I run a cross-platform achievement tracker, where the user can gather and show their achievements from xbox, psn, steam etc.
Now I want to add support for achievements attached to a users google account (google+ achievements). Can I do that through the API somehow? Been searching but can't find anything.

Does player need Google+ account?

Does the game player have to use Google+ account to use Google Play Game Services such as leader board, achivement, etc?
The player will be required to upgrade to Google+ before Play Games Services will work.

Google Play Game Services with multiple user accounts

I've just released a new version of my game with the integration of Google Play Game Services for the leaderboards and achievements. For a better understanding of my issue, here an example:
When the user connects, a popup window ask which account to use. Let's say I'm using account A. However, in the G+ app, it's account B that is connected.
When the user go to the leaderboards, he can also share a message to his friends but, that's not A's friends! That's the friends of the G+ connected account: B.
It looks like a bug for me but that's not all. Now, I have disconnected B from the G+ app and connected A instead. But it's also showing that I have no contact in my circle playing my game. That's not true. I can see in the public scores a friend of mine.
Am I misunderstanding something? Or is it a bug? For the last issue, is it just a problem of refresh? (I've tried the refresh button with no luck)