Identify spots on Mango tree

[Gini]

I am seeing black spots underneath the leaves of my Mango tree.They are very small spots and you can even remove them with your hands.
Can somebody tell me what these are?

[opabinia51]

Sounds like it might be powderty mildew. It is definately a fungal infection of some sort.

Spray the leaves with milk diluted 2:1 with water a couple of times a week for the next few months and the problem should clear up.

[Newt]

Gini, I agree that powdery mildew is a possibility. Other fungal possibilities would be algal leaf spots or anthracnose. You would really need a lab to tell you for certain. You can read Q & A #303 here.
https://ipm.ifas.ufl.edu/extension-resources/ask_extension/browse.asp?offset=300

Algal leaf spot info.
https://stri.discoverlife.org/mp/20qsearch=Cephaleuros+virescens&guide=Fruit_Pests

It might be best to read this and see if you can better id what is going on.
https://www.fao.org/inpho/content/compend/text/Ch20sec3_3.htm

Newt