You are looking for a new gardening, cleaning, auto repair or other professional services.
Take the old model of asking your friends to a new level by having an online search functionality where you can ask a question like “show me a short list of all plumbers who have good reviews from my online friends.” This can be built on top of an existing social platform, by having a professional service review option. Professional services can have a presence (a company page on Facebook for instance), and people who use them can leave reviews. When you look for a new service provider, the system can then show you the top list based on people you trust – your online friends.
Get to know what others think about the shop you’re about to enter.
An augmented reality app that shows you both before going in (by pointing the camera at the shop), and after your already inside (by pointing the camera at different spots in the shop), what others have written about it. General reviews, reviews on specific items, etc. you can, of course, leave you own review.
Children books is a particular category with special needs.
A website with book reviews specifically for children’s books, by parents. You can give your personal review and participate in the discussions.
This might be a better, faster and more accurate way to decide on what book to buy, movie to watch, etc.
Software that uses multiple sources of reviews analyzes them and creates a synopsized aggregated version of the best ones.
Make it easy to find reviews on different subjects.
Have a central place where you can find all the critics and their reviews in many areas like theater, film, gastronomy, art, etc.