We call the fruit ‘jambu’ or in Latin name it is well-known as Eugenia javanica or Syzygium samangarense. Jambu or Jambu air (local Indonesian name) is a plant species which is widely cultivated in the tropical countries, like in Indonesia.
The fruit is a bell-shaped, edible-berry, with colours ranging from white, pale green, green, pale red to red. The darker the colour, the sweeter it is. Pick the red one! I think, it is the best of all.
It is mainly eaten as fruit. Some people make jambu-pickles. In cuisine, the fruit is frequently used in salads or rujakan (Indonesia special salad).
Wanna some? ;)