Google has already released apps for iOS (iPhone) and for android phones. Now they are going to release apps for windows 7 phone.
The official Google Plus app for windows 7 phone will be a big advantage for Google Plus. Smart Phones apps will surely help Google Plus to gain more active users.
It is expected that windows 7 phone app will be available in about 7 days. It is also expected that functioning and feature of app will be almost same as functioning in iOS / Android apps.