Gacha Nebula is out and its better than Gacha Nox^^ if you still want gacha cute and i can share a link i have.
at first I thought it was because my phone is weak, but It seems like Gacha Nebula doesn't work on 32 bit phones at all, many people that use 32 bit phones have the same issue of the app closing itself shortly after opening it, I will patiently wait for the update since it's the only option I have, for now, Gacha Nebula is out of reach for me and for other 32 bit users.
same for me, I can open the game but it lags a lot and then closes itself in less than a minute after opening it, I looked at the support channels and the nebula bug reports in the Gacha nebula discord server, it seems like every 32 bit user is having issues with Gacha nebula, all that we can do is wait for the update. (You can check if gacha nebula has been updated here or here)
The same happened to me and to a lot of people, you are not the only one.
The best(and only) option is to patiently wait for the next update which will possibly fix the stability issues, once the update is out, it can be found on the itch.io page and it will also be announced on the discord server.
(I recommend that you always download it on the official itch.io page, do not trust unknown/unofficial sources claiming to have a new version of gacha nebula)