Why the animation come out very slow after 10 seconds on mobile device
it's not clear whether you're having a problem with a a mobile app created with animate or a thml5/canvas project or maybe something else.
if it's html5/canvas you can get more help by posting a link to the files on a file server. ie, not to be downloaded but ready for testing in a browser.
if it's a mobile app you can get general help.
The part about being slow after 10 seconds is unusual, unless perhaps the animation is still playing in memory.
One difference with HTML5 Canvas and AS3 animations is that when you go from part of the timeline where a movieclip is animating, to part of the timeline where that movieclip doesn't exist, it still is in memory. Make sure you have stopped any movieclips playing when you go to somewhere that it isn't needed anymore.
For poor performance on mobile that is poor from the beginning, check to see what tweens you are using. Use Classic tweens and not Motion tweens, and make sure to only use the preset tweens. A custom Classic tween will perform as badly as a Motion tween.
It's html5 canvas. I'm using preset classic tweens only. Is it related my total frame or what
Depending on what is going on, a thousands frames of animation at 60 fps on mobile may be optimistic. Are all of the graphics unique? That could fill up all of memory quickly.
If the animation is always going to be the same, you could export as an H.264 compressed .mp4 file, then you can make the animation as complex as you like.