You can look for memory leaks in your code. Maybe not destroyed events, objects when changing scenes or not optimized texture, music files usage etc etc.. I recommend you to search the forum for the keyword memory management. There are so many posts about it. You can start reading from this one: http://giderosmobile.com/forum/discussion/254/monitoring-memory-usage
I doubt it is memory issues, I don't mess with the memory much, I load stuff usually once, and put on the screen, I am having stuttering animations and random slowdowns.
If you use gtween, there is a fork on github that solved a lot of lags to me, while to be sure about being memory leaks free I'd suggest bhleaky by bowerandy. Also make sure you're not collecting garbage too often.
I am still experiencing some slowdowns, but these made a difference in my game.
If you use ttf fonts be sure to specify the characters so it caches the rendering to a texture. Otherwise every time you change text it creates a new texture/memory usage goes up.
Don't use setanchorpoint, I've heard it slows things down if over used (if someone would correct me on this it would be great).
Comments
I recommend you to search the forum for the keyword memory management. There are so many posts about it.
You can start reading from this one:
http://giderosmobile.com/forum/discussion/254/monitoring-memory-usage
Also make sure you're not collecting garbage too often.
I am still experiencing some slowdowns, but these made a difference in my game.
Don't use setanchorpoint, I've heard it slows things down if over used (if someone would correct me on this it would be great).