The older update before February it worked without lag.

Now, in february, it lags like hell.

Since new levels are added, I believe it is the cause of working levels in background, so please don't let levels hide in background, because I think the phone will load all that graphics and ruin fps.

Didn't tested all levels because of that much lag. Also, add version names like li.feb2020 to remind the current version.

Li means loot it, while feb2020 is the date.

Thanks for reporting it. I'll sort it out soon.
However. I didn't changed anything in the built version since december. The February update is just a blog post, letting you know what I'm working on right now.

More levels will come eventually, but your current problem comes from different source. 
Levels are not hidden. Please test some other game, perhaps your phone performance dropped during this time? (I mean you might installed an app that consumes a lot of resource?)

hmm, didn't changed after January? This is weird.

I will test the game now which I rooted and resented now, it may work.

Edit: looks like something created that lag. It works perfectly now. By the way, how many developers you got? I may assist you in bugs if I find, same as developing if possible but not scripting.