I recently started playing Sky Force (the new version, on Android) and got my first card, (#1 +1 hangar). After that, I managed to get two more cards, but both were #1. I think I obtained all three cards in level 1, in both the normal and hard modes. Does the first level only drop card #1, or does it drop other cards as well? Do all levels drop random cards, without taking normal/hard mode into account?
does it drop other cards as well?
Yes the drops are completely Random. What happened to you is a complete coincidence.
Do all levels drop random cards, without taking normal/hard mode into account?
All levels drop random cards, regardless of difficulty or timing.
The hanger card is one of the best card if you play a lot.
I also got 3 copies of each of the first 2 cards (and even a couple extras) before anything else. As I started moving up in ages, it seemed that when I would go back to lower ages, I would feel as though I was getting less cards per play-thru. I would often get cards that I would lose on dying (again and again), but after mastering the stage, and unlocking the next, I don't get the cards now that I can win and keep them. I now have 3 copies of each card 1-9, plus 17. I have one of each other card besides 19 and 24. I feel that you get more cards if you play the highest level available to you, or the next hardest on your max difficulty available.