What I said about Ace Patrol really also applies to Ace Patrol Pacific Skies (except that it has some upgraded graphics), so here we go again:
Ace Patrol is good fun. If you can look past the ugly mobile-phone-graphics it's a pretty deep game with plenty of strategy and tactics. Choose between several missions and complete the objectives using one or more (max 4) pilots. Make enough kills and your pilots will level up allowing them to use more/better maneuvers during battles. This can be critical later on in the game.
You'll also be able to unlock perks by completing secondary objectives. This, for example, allows crashed pilots to get right back into action after being captured by the enemy forces. And yes, better planes can also be unlocked.
Ace Patrol isn't a very long game and it's best played in short rounds, but like I said, it's good fun.