To close out the Wednesday keynote at Google I/O, SVP of engineering Vic Gundotra retook the stage to talk about Google+, which reaches its first birthday tomorrow. Gundotra announced the first native tablet app for Google+. It's an Android-centric experience available today, but Gundotra says the iPad version will have the same features and is coming soon.

It uses a sideways-swiping stream, making for a magazine-like browsing experience with the same bold photo views available on the smartphone app. The Google+ tablet app also includes a casual, lean-back interface for video Hangouts. Gundotra updated the stats on Google's social layer: 200 million users have upgraded, 150 million log in monthly, and 75 million go to Google+ daily.

Gundotra also unveiled the new Google+ Events, a long-awaited feature that will make Google+ a more useful replacement for some of Facebook's most important features.

Invitations use bold photos Google calls "cinemagrams." It integrates completely with Google Calendar, and it doesn't require email recipients to use Google+. But for Google+ users, invitations unfold like physical invitations right in the stream. It uses the Google Calendar integration to see if you're available before you RSVP.

During the actual event, Google+ Events go into "party mode." Anyone at the party who takes photos in party mode will be able to automatically upload their pics to an album for the event on Google+. Photos stream in in real time for people watching on Google+, and there's also a slideshow mode that still fills instantly as pictures are uploaded.