Guavas have the highest vitamin C amongst the tropical fruits. It has loads of antioxidants, and quite delicious when eaten fresh.
Guavas can be used in a lot of exotic recipes. We make various soup whose base is made from guava fruits. There are ready-made soup broth based on guava and they are for sale at some oriental stores.
Makes wonderful Guava jam or jelly. One of my favorite sandwiches is made from peanut butter and guava jelly.
They can be made into juice. What would the popular UC Davis POG drink be without guava. POG = Passion fruit, orange and Guava. Sometimes known as paradise drink. By itself, it makes good milkshake and other types of tropical drinks.
There are many uses for guava, the leaves can be used in the same way as bergamot. It is common antiseptic ingredient in herbal medicines. The latest news about possible use as natural pesticide looks promising.
Of course, I've tried it already. They make wonderful aromatic wines. One thing for sure, guava and citrus juice don't mix well to make wine, and I am not trying that.