Hi again, wanted to expand on my feedback as we were matched on comment club. I also want to stress up front that I know this is your first game and I think you did a phenomenal job. Some of my feedback can be handwaved as "if I had more time". :)
Jetpack Joyride is a great game, so you already had me pumped before I played it. Controls feel good. It's been a long time since I played Jetpack, so I can't remark on how accurate they are to that game. But at no point did I feel like I was out of control or that I died due to something that was not completely my fault.
The enemies are good, but could use a little more tweaking. A little bit of variable aim assist on them would probably go a long way. The rocks made it so that you couldn't just walk along the floor, you actually had to fly over them, but I did find that most of the time I could just press right against the top of the screen, only having to come down for the occasional bird that was all the way at the top of the screen. More enemy types/obstacles would probably solve that and keep things a lot more engaging as well.
I also wanted to ask if you made all of the assets yourself or if you downloaded them. Some free stuff is licensed in a way where you can use it, but you need to credit the author. Other stuff is a more open license that doesn't require credit. And stuff you paid for generally does not require credit. Or if you made it all yourself, excellent job!
All in all, an enjoyable game. MUCH better than my first game.
ps. my Highscore is 55300 now without cheesing the top of screen thing.