U r doing almost everything wrong
U r using one screen as splash onther to get device id and then third one to get data
U can easily perform these taks in only one screen by using vertical arrangements as screens
And as far as your low data loading concernes
R u using images, videos and cloudinary for storage???
Second r u calling all the data at once???
If yes then u should follow this
And provide above asked details so that we can understand your problem in a better way to help you in a better way
Thanks