> Surprisingly most of them are from Communist party of Russia.
It's not surprising at all. The communist party is the second-largest party here (polling at around ~20% in the last polls I saw). The point of the Navalny app is to highlight the candidates most likely to win against Единая Россия (Putin's party) in each district, which will usually be the candidate of the second largest party (with some exceptions).
(Just providing this information, I don't support Navalny)
It's not surprising at all. The communist party is the second-largest party here (polling at around ~20% in the last polls I saw). The point of the Navalny app is to highlight the candidates most likely to win against Единая Россия (Putin's party) in each district, which will usually be the candidate of the second largest party (with some exceptions).
(Just providing this information, I don't support Navalny)