My biggest problem with any gmaps alternative is the missing ratings option. So far I only found mapy. I am very happy with the app but wanted to check if there are any apps that might also be worth a look. Gooing in a restaurant without looking at ratings is a bit to adventurous for me.
You won’t find anything as robust as the database of reviews that Google maps has built up just due to their size and ubiquity, you’ll have to see if you can find reviews on non-maps review sites like tripadvisor, yelp, OpenTable etc.