What the other person said is true, I have a second old phone that I installed Ubuntu on. It’s really limited which phone support it though good chance you don’t have one.

Banking apps are going to check what is called “play integrity API” which checks if the device is secure locked, and not rooted. The app which allows you to use Android apps on Ubuntu touch is called Waydroid. It basically runs a full Android phone in a virtual machine. I very, very much doubt banking apps will like it. A lot of them will run on a rooted Android phone for this reason.

Other apps will work fine. A little slow, plus it’s a real battery hog to emulate the whole Android system. So if I was really trying to daily drive Ubuntu touch, I would only open the Android app for as long as I needed it and immediately shut the system down. I would try to find native apps as much as possible.