Google details its cross-platform achievements, leaderboards and cloud save for Android and iOS

"We want the whole world to play together," said developer advocate Todd Kerpelman.

"We want to make mobile games fun and engaging for everyone, and socialise with their friends through gaming."

He was talking at Google I/O about the just-announced cross-platform Google Play Game Services.

It uses Google+ to provide the player's identity, with their Circles being used to structure social leaderboards.

"People are more willing to sign in with us because they trust us not to spam their friends," said Kerpelman.

Of course, users can set what gaming information they will share in their Circles.

"Being accessible on any device is important to us," commented engineering lead, Steve Martin.

Google Play Gaming Services uses the REST API, so can connect with any connected device, but Google produces custom libraries specifically for Android and iOS.

It has a default UI for achievements or developers can create their own UI.

More important than achievements is leaderboards.

There are split into global or Public leaderboards which collect all players' scores, as well as personal or Social leaderboards using players' Google+ Circles.

Both are refreshed on a daily, weekly and lifetime basis and can be generated for different game modes.

Other, more technical features include Cloud Save. Again, this is a cross-platform feature across iOS and Android.

"We have other cloud services like Google Drive, but Cloud Save is a very simple system," said Kerpelman.

There are four game slots for data, which can be organised in different ways, either four saves or multiple components of a single save file if the save state is more complex.

Google is also adding additional anti-piracy features via back-end server so developers can return an error message if a game hasn't been downloaded from Google Play.

In terms of the real-time multiplayer feature, this supports 2 to 4 players but Android devices only.

Invites are generated through your Google+ Circles, and if some players don't have the game installed, the invite card takes you to Google Play to download the app.