If the game is paid and downladable only and you don't own it it's a sure thing you didn't play, for example.
Steam and IOS don't let people rate games they don't own.
Viewing post in Rating a game without playing
Seems like my question is answered. The answer is: "Yes, you can". You just have to agree with it to post your game here, like the playstore. Still feels bitter not being abble to answer a review even when people bash you just by looking at your game's screenshots, because they feel like (just like the playstore).