Yes, i am giving you the answer plainly, I use binance, kucoin, gate, luno, I have account on almost all major exchanges, and I can tell you that the experience are all the same.
The thing is, when you login on your Binance or Kucoin app, and after sometime, you go offline, there is a set time programmed for you to remain offline, if you return to the app before that timer is reached, you will be allowed to easily continue from where is stopped, that is, you won't be asked or required to re-login again.
But if you are offline until the set timer is reached, then anytime you open the app, you will be required to re-login.
This is a security feature which I believe is put in place to prevent other people from accessing your account when they some how or for what ever reason gained access to you phone.
Secondly, If I were to move all my coins from Binance, which exchange is the next best alternative?
Once again, do not leave your investments on an exchange, exchanges can be hacked, and when that happens, you are likely not going to get your coins back.