Features

Z2Live Platform Roadmap and Overview Z2Live is the first Multiplayer Gaming Platform for the Apple iPhone, iPod touch and iPad.

Z2Live provides game developers with a full set of services to implement social and multiplayer user experiences such as game lobbies, leader boards, friend invites, push notifications, achievements, NAT traversal, text chat, voice chat and presence.

Z2Live promotes higher price points, downloadable content and in-app purchase models that enable mobile game developers to create more attractive and more sustainable businesses.

Z2Live Platform Features

 

Note: for the latest status of game development features please review the current SDK notes.

money1. Sustainable Revenues Now, through Z2Live, you can make additional revenues through higher price points, multiplayer up sells and downloadable. Z2Live-enabled games can charge their users for access to Z2Live multiplayer gaming services. The minimum charge (set by Apple) is the Tier 1 price (for example, $0.99/month in North America).

You set up this offering through iTunesConnect and charge the user directly when he or she accesses Z2Live through your game. This revenue is through the normal Apple iTunes mechanism and comes directly to your developer business account as it would for your application downloads.

All user-specific services require an authenticated user (aka Z2Live Member), and paid services require a current and valid subscription.

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globe2. Multiplayer Gaming over the InternetAlthough some social promotion networks allow users to challenge each other to beat a high score, Z2Live allows head-to-head play on the iPhone, iPod touch and iPad over Internet connections.

2.1. Simple 2-Player MultiplayerThe simplest way to enable your game for Z2Live is to get multiplayer working over Bluetooth with Apple’s GameKit framework, using the GKPeerkPickerController and GKSession objects. Once you have your game logic working, add the Z2Live Static Library (z2lib) to the project and change:

GKPeerPickerController and GKSession

To:

Z2PeerPickerController and Z2Session

Z2Live will then manage user registration, sign in, billing, Friends List, and Internet multiplayer session.

There are a few additional functions that must be called upon application launch in order to initialize the Z2Live services and to set up Push Notification registration for Z2Live Game Invites.

shield3. User Authentication and Authorization In order to create persistent features such as friends, invites and achievements across all Z2Live-enabled games, Z2Live Authentication maintains the user database consisting of a unique user identifier and unique Z2Live Gamer Name.

Z2Live Authorization ensures that the user’s subscription is up-to-date to play your game online.

3.1. Peer-to-Peer NetworkingOne of the key and unique benefits of Z2Live is the enabling of peer-to-peer networking of iPhone and iPod touch devices, removing the cost, complexity and expense of hosting dedicated game servers.

3.2. Network Address Translator (NAT) TraversalNearly every networked iPhone and iPod touch will be connected through a Network Address Translator (NAT) device. NATs have several, severely negative characteristics when trying to connect devices in a peer-to-peer fashion.

Z2Live uses IETF standards Interactive Connectivity Establishment (ICE) protocol and the network of Traversal Using Relays around NAT (TURN) servers to establish a bi-directional UDP connection between peers.

NOTE: TCP connections between peers are not supported at this time.

3.3. Mobile Carrier Network RelaysEVERY connection between two phones that are using EDGE or 3G will require an intermediary relay, as the carriers will not support direct peer-to-peer networking through their Cellular-to-Internet Gateway.

In order to solve this problem on your behalf, Z2Live hosts TURN servers to act as a reliable relay for network connections that cannot happen directly from device-to-device.

Z2Live is the only multiplayer gaming service that enables your users to play multiplayer over a 3G connection without the need for you to host a dedicated game server.

phones4. Multiplayer Network and Multiplayer Game ServicesAlthough many developers can just use the Z2Live SDK to create multiplayer mobile games, all network services are available to developers who either have an existing network layer, or unique needs not serviced by the SDK.

All of our native iPhone client code is released under the MIT license giving you both an example implementation and full control of your code base.

4.1. Z2Live Web ServicesZ2Live Web Services such as the Friends List, Invites, Leaderboards and Achievements are accessed via HTTP using a RESTful interface. All services return data in JSON format for easy and quick parsing.

Z2Live Web Services use HTTPS for security from eavesdropping.

4.2. Z2Live Message ServiceZ2Live Message Service hosts and maintains an XMPP server cluster allowing your users to text chat in a game lobby and allowing your game to bring up the peer-to-peer connection through the ICE protocol.

The Z2Live Message Service encrypts messages with TLS preventing eavesdroppers from ruining the game experience by cheating.

friends5. Unified Friends List Each Z2Live Member maintains a Z2Live Friends List that is shared across all Z2Live-enabled games. If a member invites another member to play and that user accepts, then they are added to each other's Friends List. Members can delete Friends and block users at any time.

envelope6. Game Invites increase sales revenues from greater game take up, and more frequent play through social networking integration.

The patent-pending Z2Live Invite Service leverages Apple's Push Notification Service (APNS) to deliver Game Invites even when the user's phone is in sleep mode.
NOTE: iPod touches must be connected to a Wi-Fi access point to receive Apple's Push Notifications.

The Apple Push Notification service has three challenges that Z2Live overcomes on behalf of developers:

 
  • • Apple requires a hosted Push Notification Provider server to maintain a persistent connection to Apple’s backend servers costing developers money to host (or to partner with) providers
  • • Apple uses best-effort delivery that may not send the Push Notification and hence your game invite may not be delivered; and/li>
  • • Apple will not send a push notification to devices that do not have your game installed, eliminating the chance for one of your current users to invite another user to buy your game.
 
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6.1. Z2Live hosts the Apple Push Notification Provider server so you don’t have to. The Apple Push Notification service still requires each game to have an SSL certificate that you will upload to Z2Live.

6.2. Persistent Game InvitesZ2Live persists Game Invites in a database, ensuring that the numbers on your game’s badge are up-to-date with each notification sent, and that your game can retrieve invites upon launch even if the Apple Push Notification service has not delivered them.

chat7. Multiplayer Text and Voice ChatCommunication is critical for players to able to socialize, ask questions, suggest a different game type, tell the other players that they will “be right back”, etc. It also helps build a community; a great social experience will bring users back month after month.

There are several forms of communication that are supported through Z2Live.

7.1. Quick MessagesIf your game cannot support Text Chat because of the game play or the minimum age rating, then, at a minimum it should have a way for users to send simple, stock messages that you provide. This should be a quick overlay menu that the player can access while playing.

7.2. Text ChatFor a richer communication experience beyond Quick Messages, your game should always support Text Chat. There will be situations where Voice Chat is not possible (over a carrier’s network) or desired (between strangers in an open game session).

Text Chat is not a Z2Live requirement, but is highly recommended.

7.3. Voice ChatVoice Chat enhances the game playing experience as bringing up a virtual keyboard gets in the way of your UI. Voice Chat between friends will become a must-have feature.

However, Voice Chat has several issues that are currently being addressed.

7.3.1. Issues with Apple's Voice Chat ImplementationOne of the areas of concern is Apple's implementation itself:

1. The GameKit Voice Chat APIs send uncompressed speech and requires a lot of bandwidth per each connection (68kbps up and down).
2. The GameKit Voice Chat APIs have no ability to fill in dropped packets (there will be a gap of 1/10th of a second for each packet dropped that will be audible to a user);

These issues can be demonstrated in Apple's WiTapVoice sample released at WWDC09.

7.3.2. Technical Challenges of Voice ChatZ2Live is working on providing a robust Voice Chat solution that:

  • • Sounds good
  • • Supports more than 2 players
  • • Works over the Internet consistently
  • • Does not require a large CPU allocation

Z2Live offers a robust solution including several different CODECs optimized for quality, CPU utilization and error correction.

ribbon8. Leaderboards and AchievementsZ2Live supports leaderboards by game, location or friends list so there are multiple ways to nurture interest and competition amongst gamers. Additionally, Achievements will incent gamers to deeply explore your game, improving brand loyalty and App longevity.

lock9. Piracy MitigationThe Jailbreaking community is rampant on the Internet. Enabling Z2Live Online capabilities, an extra layer of security is added to your Application. Even if your stand-alone App is pirated, the full user-experience won’t be available unless they pay online subscription fees.

graph10. Analytics and ReportingZ2Live records metrics for your application and user events.