Here is the full list of all 27 Sky Force Anniversary achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Destroy all enemy towers on Stage 5.
Destroy 1 000 enemies.
Earn 10 medals.
Use 3 different power-ups in a single game.
Use any 5 power-ups in a single game.
Save 5 power-ups at the end of the stage.
Save 20 000 stars in your bank.
Destroy the lighthouse without touching it.
Destroy 2 500 enemies.
Destroy 10 000 enemies.
Rescue 100 people.
Rescue 500 people.
Rescue 1 000 people.
Earn 50 medals.
Earn 100 medals.
Collect 100 000 stars.
Collect 200 000 stars.
Ram through an enemy wave with your Energy Shield.
Destroy at least 15 enemies with one Mega-Bomb.
Burn through 10 enemies with your Laser.
Finish a stage with your health lower than 5%.
Rescue your friends 20 times.
Rescue 5 VIPs.
Enter the tournament.
Find all the cards.
Collect all the stars from Stage 3.
Complete Stage 8 without using power-ups.