How To Write A Google Review
You will need a Google account (Gmail email) to write a Google review.1. How to leave a review using the Google Maps app

2. Log in to your Google+ profile. If you don't have a Google+ page, you will have to sign up!
3. Open the Google Maps App on your iPhone, Android phone, iPad or tablet.
A) Type in the [business name][city].
You can also use your current location to find a business listing if
you are at the place of business while leaving the review. |
B) Select the Business listing |
C) Scroll down and click on the "Rate and Review" section |
D) Write a review about your experience, service, and so on. |
E) Finally, click on the "Publish" button. |
Source:http://www.whitespark.ca/blog/post/32-how-to-leave-a-google-review-on-mobile