Is there a fruit that you wish more people knew about? It could be for reasons of superior nutrition, or higher yield, or ecological benefits, or suitability for your local conditions, or satisfying the cravings that banana cannot, or simply deliciousness or uniqueness of flavour.
I have two that come to mind.
I've seen too many people in the rainforest buying mangos (Mangifera indica) grown far away and then planting the seeds expecting to get fruit based on ignorance or based on rumours that they heard from some neighbour's friend's cousin that mangos are starting to fruit in the area. Other than in times of exceptional drought, it doesn't work. Mangifera casturi is a species native to the non-seasonal rainforest of Borneo, and it fruits abundantly even in constant rain and damp, and yes, the fruit quality is comparable to a clonal selection of Mangifera indica and superior to many seedlings of that species. The flavour is intense and delicious. Mangifera casturi deserves far more attention.
Astrocaryum murumuru is not such a delightful fruit in comparison, but it fills an important niche. I know many people who enjoy (and even seem to develop somewhat of an obsession with) a particular spiny palm and its fruit of questionable edibility. Anything that that plant can do, murumuru can do better. The fruit is decidedly more edible (spines notwithstanding), as it doesn't contain calcium oxalate crystals that stab all of the soft tissue in one's insides, and it is more sweet and not so much a dry, greasy, starchy assault on the digestive system. The palm itself is more sturdy, less prone to falling over so long as it is able to grow a straight stem and its roots are in stable ground. The spines are far superior, truly a marvel to behold, as they easily achieve at least double the length of those found in many other palm species, with enhanced sharpness for piercing even bone. This plant is not for everyone, but it is a truly excellent choice for those who want a fruiting palm that poses a major hazard to all who encounter it. Great for planting along borders, and the neighbours won't steal the fruit.
Serviceberry:
https://en.wikipedia.org/wiki/Amelanchier
They're all over the place here, though you have a short window of opportunity to gather the fruit before the birds go apeshit and eat it all. I've had delicious jam made from it. Quite a sweet fruit, with no bitterness or tartness, unlike a lot of other wild edibles.
An excellent native option for colder climates! Which species is your favourite? :)
I don't know the species, and there are a few that are found in my area. One day I'll bring the field guide and figure it out.